Tumour

Benign Bone Tumours

Lucent Lesions

ABC

Definition

 

Expansile pseudotumor of reactive hemorrhagic tissue arising in bone

- characterised by blood filled spaces separated by fibrous tissue

 

Types

 

Primary 50%

- arise de novo 

 

Secondary 50%

- in association with other tumours 

- probably secondary to haemorrhage into 1° tumour

- GCT / chondroblastoma / osteoblastoma / osteosarcoma

- often only small component

- should treat as underlying 1° tumour

 

Site

 

Metaphysis of long bones

- proximal humerus

- femur

- tibia

 

Posterior elements of vertebra

 

Epidemiology

 

Teenagers

- 80% occur in 10-20 year range

 

F>M

 

NHx

 

Pathological fracture rare

May resolve with fracture or skeletal maturity

 

X-ray

 

Multi-loculated lesion

- eccentric

- expansile

- cortical thinning

 

ABC Proximal HumerusABC Distal Femur

 

Bone Scan

 

Usually increased uptake

- centre may have decreased uptake

 

Exclude polyostotic disease

 

MRI 

 

Haemosiderin content

- low to intermediate signal on T1 and T2

 

ABC MRI Distal Femur

 

Fluid - Fluid levels 

- due to sedimentation of RBC's & serum within the cavities

- patient must remain motionless for 10 minutes prior to the scan being performed

- allows time for sedimentation

 

 ABC Fluid Fluid Levels MRI

 

DDx

 

Fibrous dysplasia

GCT

ABC

Infection

Unicameral Bone Cyst

Osteosarcoma

 

Pathology

 

Gross

 

Blood filled spaces with fibrous septa

 

Histology

 

Cells

- haemosiderin-laden macrophages

- multinucleated giant cells

 

Septa

- fibrous stroma

- small amounts of osteoid

 

Management

 

Non operative

 

Can observe majority

- need to avoid contact sports

 

Operative

 

Indications

 

Biopsy / diagnose

Potential instability - proximal femur / spine

Pain

Recurrent fracture / debilitating

 

Options

 

Currettage and bone graft

Allograft / Joint Replacement

Embolisation

Sclerotherapy

 

Currettage and bone grafting

 

ABC Currettage and Bone GraftingABC Bone Grafting

 

Concept

 

Principles of biopsy approach

- confirm diagnosis on frozen section

- proceed to treatment

 

Indication

 

Must be able to preserve articular surface

 

Technique

 

Full and careful curettage

- intra-lesional treatment

- need to burr away all of lesion

- must take care as bone very thin

- areas of fracture not uncommon

- must beware growth plates in skeletally immature

- supplement with bone graft / bone marrow aspirate / PMMA

 

Resection and Allograft / TJR

 

Indications

 

Articular cartilage not salvageable

 

ABC Grade 3ABC Grade 3 Bulk Structural Allograft

 

Selective Arterial Embolisation

 

Indications

- preoperative in spine lesions

 

Results

 

Rossi et al Skeletal Radiol 2010

- 55 cases both spine and appedicular with N butyl cryanoacrylate

- successful in 94% cases

- a second (25%) and third (14%) embolisation required

- 2 cases of skin necrosis and one transient paresis

 

Sclerotherapy

 

Results

 

Rastogi et al JBJS Br 2006

- percutaneous sclerotherapy with polidocanol in 72 patients under II guidance

- all had histological diagnosis prior to treatment

- 84.5% clinical response

- required between 1 and 5 treatments (average 3)

- 2 recurrences successfully treated with repeat sclerotherapy

 

Varshney et al Clin Orthop Relat Research 2010

- RCT of sclerotherapy v intralesional resection of 94 ABCs

- 3 year follow up

- 93% healing in sclerotherapy group with minimal complications

- 84% healing in operative group with 3 deep and 5 superficial infections and 2 growth disturbances

 

Spine

 

Papagelopoulos et al Spine 1998

- 52 cases in the spine

- treated with extralesional and intralesional excision with bone grafting

- 10% recurrence at 10 years, all presenting within 6 months post surgery

- 4 patients had postoperative radiotherapy

- 1 died of radiation related osteosarcoma, 1 of intraoperative bleeding

- now recommend preoperative embolisation

 

Adamantinoma

Definition

 

Rare low-grade malignant tumour

- cell of origin unknown

 

Epidemiology

 

Usually second or third decade of life

 

Site

 

90% diaphysis of tibia 

 

Mandible

 

X-ray

 

Most common anterior cortex of tibia

 

Soap-bubble appearance

 

Eccentrically located

- well circumscribed

- slightly expansile

- cortical thickening

- little or no periosteal reaction

- can have late deformity

 

DDx

 

Fibrous dyplasia

Osteofibrous dysplasia / Ossifying fibroma / Osteosarcoma

Giant cell tumour

ABC

Chondrosarcoma / CS

Infection / osteomyelitis

Unicameral bone cyst

 

Diaphyseal lesion / HALFEE

- Histiocytoma

- Adamantinoma

- leukemia

- FD

- EG

- Ewings

 

Pathology

 

Two distinctly different components

 

1.  Epithelial origin 

- composed of squamous cells and epithelial pearls 

 

2.  Mesenchymal origin 

- composed of immature mesenchymal cells and spicules of dysplastic bone

- closely resembles the pattern of fibrous dysplasia and its variant ossifying fibroma 

 

Adamantinoma is considered by some to be a malignant variant of fibrous dysplasia

- resemblance of the mesenchymal component to fibrous dysplasia / ossifying fibroma

- the presence of the epithelial component makes adamantinoma a distinctly different entity

 

NHx

 

Intra-osseous, intra-cortical Stage 1A Osteosarcoma

 

Metastasis in 20% of cases

 

Management

 

Wide excision

 

Biopsy followed by wide resection

- chemo and radiotherapy ineffective

- need to address bone loss

- vascularised fibular graft / allograft / bone transport

 

Results

 

Qureshi et al JBJS Am 2000

- multicentred retrospective review of 70 cases

- average age 31, more common in males

- limb salvage attempted in 91% and successful in 84%

- up to 50% complication rate with limb reconstruction (fracture, non union)

- wide operative margins associated with lower recurrence rates

- 87% 10 year survival

 

 

 

 

 

 

Benign Fibrous Histiocytoma

Epidemiology

 

Older patients

- eipiphysis / diaphysis of long bones usually

 

Xray

 

Lytic lesion with sclerotic rim

 

Histology

 

Benign

- foam cells

- lipid filled cells

 

Treatment

 

Curette and bone graft

- chance of recurrence

 

 

Chondroblastoma

Definition

 

Rare cartilage tumour 

 

Epidemiology

 

1% of bone tumours / rare

- typically in adolescents

 

NHx

 

Usually benign

- but aggressive / frankly malignant behaviour reported

- locally aggressive

- can have pulmonary metastasis

 

Location

 

Arises in secondary ossification centre / epiphysis

- proximal tibia / knee

- proximal femur / hip

 

Develops < physis closes (unlike GCT)

 

Clinical

 

Usually painful

- may produce limitation of joint ROM

 

May produce altered epiphyseal growth in young children

 

X-ray

 

Eccentric epiphyseal 

- well-defined lucency

- thin sclerotic reactive rim

 

Proximal Tibial Chondroblastoma

 

Often internal stippled calcification

- popcorn or chicken wire calcification in 25%

- ± metaphyseal periosteal reaction

 

MRI

 

Rarely diagnostic

- many tumours will have areas of hemorrhage

- causes high signal intensity on T2

- i.e. GCT / ABC / chondroblastoma

 

Chondroblastoma Proximal Tibia MRI

 

Pathology

 

Histology

 

Stage 2 lesion typically / benign active

- active / intracapsular but with aggressive stroma

 

Chondroblastoma Histology

 

Sheets of chondroblasts and amorphous cartilage

- polygonal cells

- bluish cytoplasm

- cobblestone appearance of fine surrounding calcium like "chicken wire"

- occasional giant cells 

 

Atypical cartilage matrix

- stain +ve for S100 

- chondroid Matrix

 

DDx

  

Epiphyseal lesion in adults

- chondroblastoma

- GCT

- clear cell chondrosarcoma

- infection

- telangiectatic osteosarcoma

 

Management

 

Principles

- difficult to eradicate due to anatomic position without damaging joint or physis

- i.e. located in hip and knee close to joint surface

 

Options

 

1.  Currettage and bone graft

2.  Radiofrequency ablation

3.  Wide excision / usually necessitate allograft reconstruction or joint replacement

 

Intra - Lesional Curettage + Bone Graft

 

Chondroblastoma Intralesional Currettage and PMMA

 

Technique

- intra-articular exposure required

- meticulous debridement with burr

- local adjuvant treatment - Phenol / Liquid N2

- avoid damage to physis 

- allograft / autograft / PMMA

 

Problem

- may not be possible to prevent injury to joint due to location

 

Recurrence

 

More common in femur and foot/ankle

- should have CT chest to exclude pulmonary metastasis

- can be cured by second currettage

 

Results

 

Sallhan et al JBJS Am 2009

- retrospective review of 87 cases

- 32% recurrence by 24 months

- most likely with epiphyseal lesions

 

Ramappa et al JBJS Am 2000

- 73 patients treateed with 15% local recurrence

- 1 patient recurred 3 times

- one patient died of metastasis

- one patient was cured of metastasis by aggressive surgery

 

Radiofrequency ablation

 

Results

 

Rybak et al Radiology 2009

- 14 patients treated and available for follow up

- 12 had good relief of symptoms with no further treatment required

- 1 patient required repeat treatment

- 1 patient had collapse of chondral surface with residual tumour

 

Wide Resection

 

Indication

- usually requires resection / reconstruction of joint

- indicated for second recurrence

 

Pulmonary metastasis

- resect if possible

 

 

Chondromyxoid Fibroma

Definition

 

Benign neoplasm of cartilaginous origin composed primarily of myxoid cartilage

 

Previously thought to be Chondrosarcoma

 

Epidemiology

 

Very rare tumour

- young adults 10-30

- M:F 2:1

 

Location

 

Common upper tibia

- metaphysis of long bones

- lower limb predilection

 

Clinical

 

Tenderness

Local bulge

 

X-ray

 

Eccentrically placed metaphysis

- round or oval lucency

- well-defined sclerotic margin

- local expansion but cortex intact

- erodes / balloons the cortex

- characteristic buttress of periosteal new bone formation

 

Indistinguishable from an ABC

 

Pathology

 

Lobulated areas of spindle shaped stellate cells

- abundant myxoid / chondroid intercellular material

- multinucleated giant Cells

- merging of benign elements - hyaline cartilage / myxoid tissue / fibrous tissue

   

DDx

 

ABC 

Fibrous cortical defect

Fibrous Dysplasia

 

Management

 

Intra-lesional curettage & bone grafting

- recurrence common (40%)

- treat with wide resection

 

If Stage 3 lesion consider marginal or wide resection

 

 

Eosinophilic Granuloma

Definition

 

Langerhan's Cell Histiocytosis

- non-neoplastic disorder

- characterised by infiltration by histiocytic cells (Monocyte / macrophage lineage)

 

Group of granulomatous inflammatory processes of unknown aetiology

- involve the reticuloendothelial component of the bone marrow, parenchymal organs, and skin

 

Types 

 

E - H - L

 

1.  Eosinophilic Granuloma (70%)

- 5-20 years

- only manifestation is Osseous

- one or more lesions

 

2.  Hand-Schuller-Christian Disease (20%)

 

Think of as multiple EG's 

- more widespread granulomas

- systemic manifestation of EG 

 

Classically triad of

- diabetes insipidus  (parapituitary involvement)

- exopthalmos (orbital involvement)

- skull defects

 

Plus

- osseous lesions with mild to moderate visceral involvement

- lymphadenopathy

- hepatosplenomegaly both from EG

- skin lesions

- pulmonary disease

 

Less aggressive than LS

- 10% die

 

3.  Letterer-Siwe Disease (10%) 

- often infants < 1

- probably unrelated neoplastic condition

- rare disseminated disease of infants with fulminant course

- major visceral involvement: RES, pulmonary, anaemia

- death from hepatic failure

- less osseous involvement

 

Aetiology 

 

Unknown

 

Cell of origin is Langerhan's Cell

- ? immunoregulation disorder

- deficiency of Suppressor T-Cells

- uncontrolled macrophage proliferation 

 

Clinical 

 

Eosinophilic Granuloma (70%) 

- affects children age 4-7 years

- presentation variable & non specific

 

Back pain from vertebral lesion (most common presentation) 

 

Localised swelling (especially Skull)

 

Pain, limp & muscle wasting with pelvic or leg EG

- pathological fracture

 

Location 

 

Any bone may be affected

- skull / spine / femur / flat bones (ribs, pelvis)

 

Less common in long bones

- diaphyseal

- solitary lesion in 50%

- if multiple, < 3 lesions

 

Laboratory

 

Inconsistent & moderate elevation of ESR + anaemia

 

X-ray

 

1.  Vertebra Plana 

- compression of body

- vertebral body widened

- usually involves end plate rather than neural arch

- discs intact

 

DDx

- Ewings

- MM, Mets, Lymphoma, Leukaemia

- ABC

- infection

 

2.  Long Bones 

 

Diaphyseal osteolytic lesion

- thin sclerotic rim with endosteal scalloping

- cortical expansion with overlying periosteal reaction

- appearances vary according to stage of healing

 

DDx

- HALFEE

 

3.  Skull 

- most common site

- multiple punched out lucencies

- coalesce to give geographic skull

- typically bevelled edge appearance to lesion

 

MRI 

 

Lesion is low signal on T1 & high signal on T2 

- enhancing brightly with gadolinium (good discriminator)

 

DDx

 

Need to rule out HSCD or LS

- bone scan & skeletal survey

 

Pathology

 

Defect filled with lipid-laden histiocytes with eosinophilic cytoplasm

- plasma cells (blue with cartwheel nucleus)

- eosinophils (pink with bilobed nucleus)

- plasma cells with occasional eosinophils

 

Cytoplasm of cells contains specific Inclusion X bodies 

- same as Birbeck granules in Langerhans Cell 

- visible under EM

 

Positive staining for S100

 

NHx

 

Usually self-limiting

- fibroblasts obliterate histiocytes & inflammatory response

- tissue replaced by bone

 

Management

 

Vertebroplanar in infant

- self limiting

- will resolve

- no treatment required

 

Surgical indications

- symptomatic

- progressive

- neurological deficit

- at risk of pathological fracture

 

Options

 

1.  Intralesional steroid

 

Rimondi et al Skeletal Radiol 2009

- CT guided percutaneous intralesional methylprednisone

- success in 17/19 patients

- remaining two found to have systemic disease

 

Yasko et al JBJS Am

- 35 lesions

- resolution in all but one

- 97% success

 

2.  Curettage and bone grafting

 

HCSD & LSD

 

Systemic treament / chemotherapy

- radiotherapy for localised lesions

- alkylating agents + steroids

- poor results if recurrence within 1 year

 

 

Fibrous Cortical Defect

AKAFibrous Cortical Defect Femur Fracture

 

Non Ossifying Fibroma

 

Definition

 

A hamartomatous defect in the metaphyseal cortex of skeletally-immature adolescents

 

Fibrous cortical defect 

- < 2cm in diameter

 

Non ossifying fibromas 

- > 2cm

 

Aetiology

 

Localised defect in cortex of long bone

- failure of bone to form

 

Epidemiology

 

Most common skeletal lesion

- 35% of young children

- most common cause of pathological fracture in children

 

NHx

 

Self limiting

- usually ossify by early adulthood

- ? become bone islands

 

United Non Ossifying Fibroma

 

Location

 

Distal femur

Distal tibia

 

Clinical

 

Child

- incidental finding

- pathological fracture

 

X-ray

 

Non-Ossifying Fibroma 

- > 2 cm

- eccentric metaphyseal lesion

- sclerotic margin

- slight expansion of cortex

- usually < 1/3 diameter of bone

 

Fibrous Cortical Defect

- < 2cm

- small cortical lucency 

- sharply defined border

 

Pathology

 

Fibroblasts in whorling fibrous stroma

- multinucleated giant cells

- no bone formation

 

Management

 

Biopsy

 

Usually don't require biopsy

- biopsy if uncertain

 

Fibrous Cortical Defect

 

Management

 

Serial observation

- xray yearly

- 35% of children have them

 

Non Ossifying Fibroma

 

Indication for surgery

- large lesions

- > 1/2 diameter of bone

 

Management

- curettage & bone graft

 

Pathological fracture

 

Management

 

1.  Treat closed if possible

- fracture heals in normal length of time

- lesion may heal with fracture union

 

2.  If persists, curettage / graft

 

Fibrous Cortical Defect Femur FractureNon Ossified Fibroma ORIFNon Ossified Fibroma United

 

 

 

 

 

 

Fibrous Dysplasia

Definition

 

Developmental hamartoma in which areas of the skeleton fail to mature normally

- remain indefinitely as immature, poorly mineralized trabeculae

 

Pathology

 

Hamartoma of bone and fibrous tissue

 

McCune - Albright's Syndrome

 

Rare triad of

 

1.  Fibrous Dysplasia

 

2.  Cafe-au-Lait Spots

- irregular 'Coast of Maine'

- compare with regular outline of 'Coast of California' in NF

 

3.  Precocious puberty

 

Malignant transformation

 

Monostotic 0.4%

 

Polyostotic / Albright's 4%

- OS / FS / CS

 

Inheritance

 

Usually non genetic inheritance

 

Osteofibrous Dysplasia

 

Only Tibia

- precursor Adamantinoma

- more dense with trabecular pattern

- plump rimming osteoblasts

 

Types

 

1. Monostotic 85%

 

2. Polyostotic 15%

 

3. Associated with endocrinopathy

- Vit D Resistant Rickets

- Hyperthyroidism

- DM

- Acromegaly

- Cushing' s syndrome

 

Location

 

Any bone

 

Femur

- involved in 90% polyostotic

 

Tibia

 

Skull / maxilla / ribs

 

NHx

 

Usually diagnosed in children and adolescents

 

Remains relatively unchanged throughout life

- in keeping with developmental abnormality 

 

Clinical

 

Monostotic

- incidental finding

 

Fibrous Dysplasia Pelvis

 

Polyostotic

- usually present in childhood

- pain (indicates microfracture)

- pathological fracture

- limp

- deformity

 

X-ray

 

Intramedullary diaphyseal lesion

- 'ground glass appearance'

- tissue that is more lucent with a similar to the density of cancellous bone

- homogeneous with no visible trabecular pattern

 

Thinned, slightly bulged cortex

- ± endosteal scalloping

 

± Angular deformity at site of lesion

 

Coxa vara of proximal femur

- Shepherd's Crook deformity

- secondary LLD

 

Fibrous Dysplasia Hip0001Fibrous Dysplasia Hip0002

 

Sabre tibia

 

CT

 

Fibrous Dysplasia CT

 

Bone Scan

 

Skeletal Survey

- mono v polyostotic

- look for other lesions

 

MRI

 

Low T1 SI

Low - High T2 SI

 

Pathology

 

"Chinese letters"

- strands of osteoid & bone arising from fibrous stroma

- irregularly shaped bony trabeculae in fibrous stroma

 

Management

 

Principles

 

Basic rule is don't operate unless deformity

 

Any morcellised bone graft is resorbed

 

Guille et al JBJS Am 1998

- 100% resorption of bone graft with recurrence of lesion

- osteotomy and fixation with reconstruction nail mainstay of treatment

 

Medical Management

 

Bisphosphonates

- to relieve pain

 

Results

 

Chapuriat et al Bone 2004

- marked reduction in pain

- some resolution / filling in of lesions

 

Proximal femur

 

Aim 

- stabilise diaphysis

- prevent coxa vara

- try to wait until skeletal maturity

 

Management

 

1.  Valgising osteotomy

 

2.  Plate (immature) / Reconstruction Nail (mature)

 

Results

 

Yang et al Acta Orthop Trauma Surg 2010

- 14 cases with valus osteotomy / currettage / allograft and reconstruction nail

- good restoration of alignment with improvement in LLD 

- no recurrent fractures or progression of deformity

 

Sabre tibia

 

Management

 

Osteotomy + IM nail

 

THR

 

Beware large cysts

 

Fibrous Dysplasia Hip CT

 

Giant Cell Tumour

Definition

 

Benign lesion with a wide spectrum of behavior characterized by stromal cells and giant cells

 

Epidemiology

 

Common

- 20% of benign tumours

 

More common females

- F:M = 1.5:1

- most tumours M>F

 

Usually patient in 20's

- usually after skeletal maturity

- 3% < epiphyseal closure

 

Can behave in malignant fashion

 

Location

 

Epiphysis

 

Knee 50% 

- distal femur

- proximal tibia

 

Remainder

- distal radius

- sacrum

- vertebral bodies (anteriorly like EG compared with ABC/OO)

 

GCT Distal RadiusGCT Distal Radius CT

 

Clinical

 

Involved joint has

- dull ache

- effusion

- muscle atrophy

 

Pathological fracture common

 

X-ray

 

GCT Distal Femur Xray

 

Well-defined defect in epiphysis & metaphysis

- no sclerosis around lesion

- sub-articular with extension into subchondral bone

 

May extend into articular cartilage

- unique ability

 

Minimal periosteal reaction

 

± Cortical breach & soft tissue extension

 

DDx

 

Brown's tumour / hyperparathyroidism

 

MRI

 

Show cortical destruction & soft tissue extension

- soft tissue extension suggest stage 3 aggressive

 

GCT Distal Femur MRI0001GCT Distal Femur MRI0002

 

Bone Scan

 

Mono v polyostotic

 

Bloods

 

Ca++ / Se PO4

- rule out Brown's tumour

 

ESR 

- Osteomyelitis & EG

 

Pathology

 

Giant Cell Tumour Histology Nephron GNU Free Documentation License Version 1.2 httpwww.gnu.orgcopyleftfdl.html

 

Two Cell Types

A Multinucleated Giant Cells 

- similar to osteoclasts

- likely reactive

B.  Small Stromal Cells 

- ? the actual tumour 

- probably osteoblast derivatives

 

Background of fibrous tissue

- normal mitoses usually seen

- areas of spontaneous necrosis (rare for benign tumours)

- thin cortical shell

 

Campanacci Stagin

 

Stage I Latent (15%)

 

Sclerotic Rim

- asymptomatic

- inactive on bone scan

- histologically benign

 

Stage II Active (70%)

 

Expanded cortex but no breakthrough

- symptomatic

- often have pathological fracture

- active on bone scan

- histologically benign stromal cells

 

Stage III Aggressive (15%)

 

Rapidly growing mass

- cortical perforation with ST mass

- symptomatic

- extensive activity on bone scan

- histologically benign

 

Malignant

- rare form

- sarcomatous lesion contiguous with benign GCT 

 

Prognosis

 

Previously said 10% metastasize

- many of these would now be called MFH

- for it truly to be giant cell have to see typical appearance of GCT in metastasis

 

Primary malignant GCT better prognosis than malignant change in recurrence

 

DDx

 

ABC / UBC

Chondroblastoma

Clear cell sarcoma

Telangiectatic Osteosarcoma

Synovial cyst of OA / Geode

PVNS 

OM (brodies abscess)

 

Because there are 2 malignant tumours which can mimic

- all need careful staging and biopsy

 

Management

 

Staging

 

Biopsy usually performed

 

Options

 

1.  Currettage + bone graft / PMMA
2.  Wide excision + allograft / arthroplasty

3.  Adjuvant treatment

 

Grade I & II

 

Management

 

Currettage and PMMA

- extended curette with high speed burr

- saucerisation 

- bone graft under subchondral bone

- adjuvant PMMA (works by thermal necrosis)

 

GCT Distal Femur PMMA

 

Results

 

Blackley et al JBJS Am 1999

- treatment of 59 patients with high speed burr and autograft / allograft

- 12% local recurrence

 

Becker et al JBJS Am 2008

- demonstrated reduced local recurrence with the use of PMMA

 

Bauer et al JBJS Br 2006

- treatment of recurrences with repeat currettage and PMMA

- 13/15 successful after one treatment, remainder after 2

 

Grade III & Recurrence

 

Management

 

Wide resection & osteochondral allograft / arthroplasty + adjuvant DXRT

 

Indications

- extensive soft tissue tumour

- extensive cortical destruction / pathological fracture

- joint destruction

 

Results

 

Bell et al J Arthroplasty 1994

- fresh osteochondral allograft for distal femur in 16 patients

- 3 revisions and 1 late infection

- 8/13 assessed were good or excellent

 

Unresectable

 

DXRT

- i.e. sacral and pelvic GCT

 

Bisphosphonates

 

Theory

 

GCT rich in osteoclast derived cells

 

Results

 

Balke et al BMC 2010

- use of bisphosphonates in aggressive primary / recurrent / metastatic GCT

- no increase in size in inoperable tumours

- no recurrences in tumours that had repeatedly recurred

- lung metastasis did not increase in size or number

 

Recurrence rates

 

Enneking

- grade 1 = negligible recurrence

- grade 2 = 20%

- grade 3 = 70%

- grade 3 + adjuvant = 20%

 

Metastases

 

Lung metastases occur in 2%

- lesions slowly progress ie benign in nature

- usually treat with surgical resection

- consider GCT benign if pulmonary metatasis histologically benign

- regular CXR in patients with GCT

 

 

 

 

Haemangioma

Definition

 

Hamartomatous proliferation of vascular tissue

 

Epidemiology

 

Commonest tumours in infancy & childhood 

- usually superficial

 

Types

 

Capillary

- majority

- small nodules of capillary sized vessels lined by flattened endothelium

- nodules clumped in lobular pattern

 

Cavernous 

- less common

- usually larger & involve deeper structures

 

Associations

 

1.  Klippel Trenaunay Weber Syndrome 

- hemihypertrophy with underlying venous malformations

- secondary to increased angiogenesis

- UL, LL or both affected

- usually unilateral

 

2.  Maffucci Syndrome

 

3.  Sturge-Weber

- rare congenital / not hereditary

- often facial capillary malformation

- more extensive hemangiomata

- mental retardation / seizures / hemiparesis  

- hemiatrophy

 

Site

 

Cutaneous

Subcutaneous

Intramuscular

Intra-osseous

 

Clinical

 

Ache

Limb heaviness

Lesions in the skin - distended bluish discoloration 

Deeper intramuscular lesions present as a tender mass

 

X-ray

 

Soft-tissue lesions

- same radiodensity of muscle

 

Often small calcified nodules / phleboliths

- circular pattern with a radiolucent center (due to recanalization) 

- same as those seen in the pelvic veins of multiparous females

 

MRI

 

Exceedingly bright signal 

- due to the high fluid content of the lesion 

 

CT

 

Polka dot appearance due to section through the vessels

 

These lesions often penetrate the bone and have a large soft tissue component

 

Management

 

As pain / disability demands

- often observation

 

Soft tissue Hemangioma

 

Hemangioma Soft TissueHemangioma Embolisation

 

Non-operative

- stockings

- simple analgesia

 

Operative 

- resection

- embolization

 

Beware rare cases of malignant change

 

Intraosseous Hemangioma

 

Epidemiology

- F:M = 2:1

- incidence increases with age

- 0.8% of 1° bone tumours

- commonest sites are spine (especially thoracic) & skull

 

X-ray

 

Characteristic finding is the coarsened vertical trabeculae

 

Spine 

- honeycomb or corduroy cloth appearance

- in spine this finding is usually sufficient for the diagnosis

 

Skull 

- spoke-wheel configuration

 

CT

 

Characteristic finding is multiple dots "polka dots"

 

MRI 

 

Usually bright on T1 & T2 images because of fat content

- areas of trabecular thickening will have low signal intensity

 

Hemangioma Spine

 

 

 

Osteofibrous Dysplasia

Definition

 

Congenital hamartomatous lesion

- occurs almost exclusively in the tibia or mandible

- striking resemblance to fibrous dysplasia

- thought by many to be a variant of that condition

 

Location

 

Anterior cortex of tibial diaphysis

Mandible

 

Clinical

 

Young child

 

Anterior bow or mass in tibia

 

Pathological fracture common

 

X-ray

 

Multiple small radiolucent lesions

 

Rim of reactive bone

 

DDx

 

Adamantinoma

Fibrous Dysplasia

EG

Ewing's

Periosteal OS

 

Management

 

Issue

 

Risk of adamantinoma in lesion

- recommended excision of all lesions

 

Currettage alone

- 100% recurrence rate

 

Results

 

Lee et al JBJS Br 2000 

- review of 16 patients with osteofibrous dysplasia tibia

- 6 treated initially with currettage / all recurred

- treated with segmental excision and management of bone defect

- some small lesions

- others requiring fibular graft or bone transport

- 3 confirmed cases of adamantinoma

- no recurrences

- recommend excision in all cases

 

 

 

Periosteal Chondroma

Definition

 

Metaphyseal Enchondroma

 

Site

 

Arise from the metaphyseal cortex of long bones

- most common in the proximal humerus

 

Histology

 

Difficult to DDx from Chondrosarcoma

 

Masses of cartilage nestling in a shallow crater in the periphery of the cortex

 

NHx

 

Don't ossify

- remain as immature cartilage

 

No malignant potential

- Don't transform into CS

 

DDx

 

Juxta-cortical chondrosarcoma

Periosteal osteosarcoma

 

Unicameral Bone Cyst

AKAUnicameral bone cyst femur

 

Simple Bone Cyst

 

Definition

 

A simple bone cyst is a solitary cavity containing clear fluid

- originating in the metaphysis of growing children

- adjacent to the metaphyseal aspect of the growth plate.

 

Aetiology

 

Unknown pathological origin

- likely secondary to venous obstruction / hypertension

- probably not neoplastic

- occurs during growth

 

Epidemiology

 

Children

 

M 2:1

 

Location

 

Proximal metaphysis 

- humerus 67% 

- femur 15%

 

Often immediately below physis

- metaphyseal side

 

Can occur in os calcis

 

Types

 

Active

- adjacent to physis

 

Latent

- separated from physis by normal bone

 

Clinical 

 

Present with pain caused by pathological fracture

- commonest presentation 75%

 

X-ray

 

Metaphyseal near physis

- well-defined lucency 

- thin sclerotic rim

- usually central

- thinned cortex with slight expansion

- thin internal septa

- can be multi-loculated

 

Fallen-Leaf sign 

- with pathological fracture

- "Classic" sign

- pathognomonic because indicates that the lesion has no matrix & is fluid filled 

 

DDx ABC

 

ABC

- eccentric (v central)

- width > physis

- can be very difficult to tell

 

Pathology

 

Pressure

- they have an arteriolar pressure curve

- cyst pressure is higher than venous pressure

 

Fluids

- contain high levels of prostaglandins

- contain high levels of alkaline phosphatase

 

Gross

 

Thin cyst lining with fine septae

- contains clear fluid compared with ABC

 

Histology

 

Thin fibrous layer of CT 

- cells resembles synovial cells

- few multinucleated giant cells

 

NHx

 

Tend to become latent

- resolve in adulthood

- may resolve post fracture

 

Management

 

Issue

 

Will eventually heal, but tend to fracture up to 4 times on average

 

1.  Humerus

- fractures will heal in sling

- must then avoid non contact sports

- difficult to tell child not to play sports for many years

 

2.  Femur

- want to prevent fracture

- avoid morbidity / deformity

 

Options

 

Observe

Inject HCLA

Inject bone marrow aspirate

Currettage and bone graft

Cyst drainage

- cannulated screws

- IM rods

ORIF

 

Observation

 

Inactive & small

 

Aspiration and injection HCLA

 

Technique

 

Aspirate initially

- if aspirate blood / treat as ABC / biopsy

- if aspirate fluid / simple cyst

 

Inject contrast

- ensure not loculated

- if it is, need to inject all parts of cyst

 

Inject methylprednisolone

- steroid blocks PGE

- methylprednisolone 50 - 200mg

- second needle as vent

 

Results

 

Rud et al Orthopaedics 1991

- 11 UBC treated with injection of methyprednisolone

- 2 required second treatment

- 5 cysts resolved completely whilst 6 resolved sufficiently that fracture was no longer a risk

 

Bone marrow injection

 

Technique

 

GA / Aspirate from bone marrow

- inject into cyst under II

 

Results

 

Rougraff et al JBJS Am 2002

- 25 cases treated with percutaneous bone marrow aspirate

- combined with demineralised bone matrix

- 5 recurrences

 

Wright et al JBJS Am 2008

- RCT of bone marrow aspirate v HCLA in 77 patients followed for 2 years

- 42% in the methylpredisolone group healed

- 23% in the bone marrow group healed

 

Curettage + Bone Graft

 

Results

 

Hunt Orthopedics etal 2009

- 21 proximal humeral cysts

- 75% union rate

 

Cyst drainage

 

Concept

- venous hypertension cause of cyst

- if allow cyst to drain, will heal

 

Options

- cannulated screw into lesion

- TENS nails humerus

- IMN femur

 

Results

 

Linhart et al Orthopedics and Traumatology

- 21 proximal humeral cysts

- distal to proximal flexible nails

- 95% union rate

 

Hou et al JBJS Am 2010

- humeral cysts

- 11/12 healing with currettage / synthetic bone graft / cannulated screw

 

Specific Regions

 

1.  Humeral Unicameral Bone Cysts

 

Treat fractures non operatively in sling initially

- need treatment if debilitating

 

Options

1.  Non operative / avoid contact sports and wait

2.  Injection HCLA

- minimally invasive, perform in OT

3.  Percutaneous TENS nails

 

2.  Proximal Femur Unicameral Bone cysts

 

Pathological fracture

- treat in traction / spica if minimally displaced or very young

- otherwise paediatric sliding hip screw

- reconstruction nail if > 15 years

 

Non fractured but high risk

- trial injection

- paediatric hip screw if < 15 with bone grafting

- IMN if > 15

 

Unicameral Bone CystUnicameral Bone Cyst IM Nail

 

                   

 

 

 

 

Sclerotic Lesions

Bone Infarct

Epidemiologybone Infarct Knee

 

In caisson workers / divers

Sickle cell anemia

Long term steroid

 

Aetiology

 

May sometimes be a degenerating lipoma of bone

 

DDx

 

Chondroblastoma / Chondrosarcoma

- if in metaphyseal region

 

Enchondroma

 

Bone island

 

Bone Scan

 

No increased uptake

 

Histology

 

Mineralisation of necrotic marrow elements

 

Prognosis

 

MFH may arise from long standing bone infarcts

 

 

Enchondroma

 

DefinitionEnchondroma Hip

 

Benign intramedullary cartilage lesion

 

Aetiology

 

Enchondroma are presumed to be remnants of hyaline cartilage

- derived from the epiphyseal growth mechanism that failed to undergo enchondral ossification

 

Epidemiology

 

10% of benign bone tumours

 

Young adults

 

Stop growing in adults and calcify

 

Malignant transformation 

 

Rare

- enchondroma in hands and feet always benign

- benign looking enchondroma located centrally may be malignant

 

Age 

- in general not malignant prior to maturity

 

Bone scan not helpful

 

Histology not helpful

 

Location

 

Intramedullary

 

Start near physis (metaphyseal) but may become diaphyseal

 

Involves any bone formed by endochondral ossification

- especially tubular bones of hands & feet

- 50% in hands, especially phalanges

- 10% in feet

- also common femur, humerus & ribs

 

Can have periosteal chondroma

- surface long bones

- calcified matrix

- well demarcated cortical defect

 

Clinical

 

Usually incidental finding

- may be patholological finding

 

X-ray

 

Enchondroma Distal Femur0001Enchondroma Distal Femur0002

 

Intralesional calcification in adults

- especially in long bones

- punctate, stippled calcification and broken rings

 

Shoulder EnchondromaShoulder Enchondroma CT

 

No periosteal reaction

 

Suspicious Lesion (5)

 

Chondrosarcoma

 

1. X-ray appearance

- scalloping (endosteal erosion)

- periosteal reaction

- fluffy calcification

 

2.  Size > 6-10 cm rarely benign

 

EnchondromaEnchondroma

 

3.  Peripheral vs central 

- central pelvis / shoulder girdle more concerning

 

4.  Age - malignancy rare <20

 

5.  Solitary vs Olliers

- benign more cellular in Olliers

 

Bone Scan

 

Usually increased uptake

 

MRI

 

MRI Enchondroma0001MRI Enchondroma0002

 

Pathology

 

Composed of masses of hyaline cartilage without characteristic architecture

- typically bland cartilage

- no pleomorphism / anaplasia / hyperchromasia

- hand lesions tend to look more hypercellular & pleomorphic

 

Enchondroma Nephron GNU Free Documentation License Version 1.3

 

Can be very difficult to distinguish between low grade chondrosarcoma and enchondroma

 

DDx

 

Long Bone with Intralesional Calcification

1.  Enchondroma

2.  Bone infarct 

3.  Chondrosarcoma

 

Phalanx

- epidermoid inclusion cyst

- glomus tumour

 

Staging

 

Plain radiograph

- biopsy usually not required

 

Management

 

Options

 

1.  Observation

 

Biopsy

- enlarging

- becomes painful

 

2.  Prophylactic Resection

 

Doesn't require prophylactic resection because

 

A.  Malignant transformation very rare <1%

- usually in pelvic or shoulder girdle

 

B.  Transform to chondrosarcomas

- low-grade, slowly growing and painful

 

3.  Hand fracture through enchondroma

 

Allow to heal non operatively if possible

Curettage and bone graft once united

 

Enostosis

AKA

 

Bone island

 

Definition

 

Hamartomatous lesion 

- island of mature cortical bone found in the midst of normal cancellous bone 

 

Epidemiology

 

>10

 

M=F

 

Clinical

 

Asymptomatic x-ray finding (usually in adolescents)

 

X-ray

 

 

Shoulder Bone Island

 

Sharply-circumscribed cortical densities

- usually round or oval in shape with smooth, regular borders

- sharp / narrow zone of transition from lesion to cancellous bone 

- no evident reaction to the process

 

Range in size from a few mm to several cm

- more commonly less than 1 cm in diameter

 

CT 

 

Even cortical texture

 

Management

 

Observation

 

Osteopoikilosis 

 

Multiple bone islands

- sclerosing skeletal dysplasia

- AD inheritance

- hips / pelvis / sacrum / femur / humerus

- characteristically periarticular

- lesions asymptomatic and cold on bone scan

- malignant transformation extremely rare

 

 

 

 

 

Melorheostosis

Epidemiology

 

Rare, non-hereditary lesion

- 1: 1 000 000

 

M = F

 

Apparent in early childhood and even in the first few days of life

 

About 50% of persons affected will develop the symptoms by 20 years of age

 

Aetiology

 

Unknown

 

Theory 

- lesion arises from an abnormality of the sensory nerve of the affected sclerotome

- sclerotome is a zone of the skeleton supplied by an individual spinal sensory nerve

- represents a basic unit of vertebral embryonic development.

 

Clinical

 

Pain, joint stiffness, and progressive deformity

- mainly the bones of the extremities and pelvis

 

LLD, deformity

 

Joint contractures

- secondary to extraosseous bone formation

 

Can cause spinal stenosis

 

Can have extensive ST masses, which can ossify

 

X-ray

 

Sclerotic lesions of bones 

- undulating cortical hyperostosis

- look like wax dripping down the side of a candle

 

Bone Scan

 

Increase uptake

 

MRI

 

Heterogenous

- mix of osseous, fibrous, adipose, cartilage

 

Biopsy

 

Variable degree of marrow fibrosis

- with markedly irregular bone with mixed areas of lamellar and woven bone

- mixture of osteocartilagenous, fibrovascular, and adipose tissue is seen in the soft tissue masses

 

NHx

 

The clinical course is slowly progressive

 

Severe symptoms may require treatment by sympathectomy or even amputation

 

Isolated cases of malignancy have been reported in association with melorheostosis

- one osteosarcoma and one malignant fibrous histiocytoma

 

 

 

 

Multiple Enchondromas

Multiple enchondroma occur in two circumstances

 

1. Ollier's

-  distributed symmetrically in an extremity

 

2. Maffucci's syndrome

- randomly distributed throughout the skeleton

- in association with hemangiomas

 

Ollier's Disease

 

Site

 

Enchondromas symmetrically distributed through an extremity

 

Usually unilateral and monostotic

 

Epiphyseal, metaphyseal or diaphyseal

 

Inheritance

 

Not heritable / embryonal disorder

 

Problems

 

1.  Often associated deformation of growth

- LLD

- bowing wrist

- bowing elbow

 

2.  Malignant transformation

- 25% at 40 years

 

Maffucci's Syndrome

 

Clinical Features

 

Multiple enchondromas 

- randomly distributed

- associated with hemangiomas

 

Problems

 

1.  100% risk of malignant transformation 

- usually long latent phase

- 30 - 50 years of age

 

2.  Associated with other tumours

- visceral carcinoma

 

3.  Cutaneous hemangiomata

- bring diagnosis to attention

 

4.  Skeletal deformity

- short tubular bones hands & feet

- long bones of UL / LL

- one side of body usually more severe

- palpable mass

- LLD

- bowing of forearms

- varus / valgus of legs

 

Management

 

Osteotomy through lesion to correct angulation

 

Epiphyseodesis or limb lengthening

 

Curettage & grafting of large lesions interfering with function

 

Need lifetime vigilance for tumour transformation

 

Multiple Hereditary Exostosis

AKA

 

Diaphyseal Aclasis / Multiple Osteochondromas

 

Definition

 

Heritable skeletal dysplasia

 

Epidemiology

 

AD with variable penetrance (96%)

 

Malignant Transformation

 

Incidence of malignant transformation much higher 

- 10% overall

- 1 % / year

 

Chondrosarcoma (CS) > Osteosarcoma (OS)

 

Secondary CS has better prognosis than primary CS prognosis

 

Danger areas / central

- pelvis

- scapula

- proximal humerus

- proximal femur

- spine

 

Clinical

 

Mildly short stature

 

Nerve compressions

 

Upper Limb

 

Scapular involvement (winging)

 

Forearm involvement

- ulnar deviation of wrist

- loss of pronation / supination

 

Lower Limb

 

LLD

Valgus knees

Valgus ankle

CPN compression

 

Multiple OsteochondromasMultiple Osteochondromas

 

X-ray

 

1.  Coxa Valga

- neck short & broad

 

Hip OsteochondromaOsteochondromas Hip

 

2.  Genu valgum

 

Osteochondroma KneeOsteochondroma Knee Lateral

 

3.  Ankle valgus

- fibular shortening with valgus distal tibia

- wedge-shaped distal tibial epiphysis

- leads to valgus talar tilt in abnormal mortise

 

Osteochondroma Ankle

 

4.  Forearm 

- ulnar shortening with radial bowing

- ulnar deviation of wrist

- radial head dislocation

 

Osteochondroma ElbowOsteochondromas Forearm 1Osteochondromas Forearm 2

 

Osteochondromas WristOsteochondromas Wrist Lateral

 

Histology

 

Exostoses tend to be more disorganised with bosselated cartilage cap

 

Management

 

Principles

 

Excision of symptomatic osteochondromas

Removal of suspicious lesions

 

Sites

 

Forearm

 

Most disability 

- maybe little functional loss

- pronation / supination decreases with age

 

No evidence that OT will improve function

- distal radial osteotomy / hemiepiphyseodesis

- lengthening of ulna

- excision of local osteochondromas

 

Ankle

 

Chin et al JBJS Am 2000

- demonstrated that early removal in full of osteochondroma

- allowed remodelling of deformity

 

1.  Guided growth

- slow growth medially / screw or 8 plate

- allows lateral fibular growth to correct valgus

 

2.  Supramalleolar osteotomy / Ilizarov correction

- deformity correction

 

Knee

 

High incidence of valgus tibial deformity

Case reports of popliteal pseudoaneurysm

 

Osteochondromas Valgus KneeOsteochondromas Knee Osteotomy APOsteochondromas Knee Osteotomy 2

 

 

 

Nora's lesion

 

It was described in 1983 by Dr. Nora, and is sometimes called Nora's disease or Nora's lesion

 

Definition

 

Bizarre parosteal osteochondromatous proliferation 

 

Epidemiology

 

Rare lesion 

- occurs most commonly in the hands and feet

 

Adults in their 20's and 30's

 

Males = Females

 

Site

 

Most common in the hands 

- followed by the feet

- long bones (commonly of the upper extremity)

- skull, jaw

 

Hands

- proximal and middle phalanges

- metacarpals

 

NHx

 

Grows rapidly

- aggressive features on imaging 

 

Clinical

 

Mildly painful mass 

- seems to increase in size over many weeks or a few months

- usually no history of trauma

 

X-ray

 

Bony mass

- well defined margins 

- seen to be applied to the surface of the bone

- it may project into the soft tissues

- lacks the characteristic orientation away from the nearby physis that is seen in osteochondromas. 

 

Wide base

- may appear pedunculated

 

Matrix

- mature, trabeculated bone

 

CT

 

Osteochondromas

- cortex and medullary cavity of the bone is continuous with the cortex and medullary cavity of the lesion

 

BPOP / Nora's

- cortex and medulla not contigous with cortex

- no cartilage cap

 

MRI

 

Typical tumour picture

- high SI on T2

- low SI on T1

 

No cartilage cap

 

DDx

 

Parosteal / periosteal OS

 

Pathology

 

Gross 

- nodular surface covered with glistening cartilage.  

- bone in the lesion has a distinct blue tint 

- The cut surface of the lesion bleeds freely

 

Histology

 

Very cellular cartilage

- proliferation of bizarre fibroblasts

- disorganized bone with spindle shaped fibroblasts in the intertrabecular spaces

 

Confusion with 

- chondrosarcoma

- fibrosarcoma

- low grade parosteal osteosarcoma

- conventional osteosarcoma.  

 

NHx

 

Lesion is benign 

 

Management

 

Wide excision

- limits local recurrence

 

Recurrence

- may recur locally in as many as 50% of cases

- seen from 2 months to 2 years after surgery

 

 

 

 

Osteoblastoma

Epidemiology

 

Uncommon

 

< 1% Primary bone tumour

 

Young boys

- second decade

 

Location

 

Similar to OO

 

Spine 30%

- especially posterior elements

 

Long bones 35%

 

Clinical

 

Back or limb pain

- pain less severe than OO

- not dramatically relieved by aspirin

 

Limp

 

Scoliosis

 

X-ray

 

Spine

- difficult to see

- irregular cortex

- sclerotic or loss of pedicle

- enlargement of spinous process

 

Long Bone

- less diaphyseal occurrence than OO

- more common meta-diaphyseal

- large faintly radiolucent lesion

- thin reactive rim

- may be expansile

 

CT 

 

Demonstrates spinal lesion well

- bone expansion

- intralesional stippled ossification

 

Osteoblastoma CT 1Osteoblastoma CT 2

 

Bone Scan

 

Uptake +++

 

DDx

 

Osteoid osteoma

- < 2 cm

 

Pathology

 

> 2cm diameter

- less reactive rim

- otherwise identical to OO

- osteoid

 

Can be difficult to differentiate from OS 

- may also see changes of ABC

 

NHx

 

On rare occasion have acted aggressively

- bone destruction & soft tissue extension

- however don't metastasise

 

Management

 

Options

 

1.  Excision with wide margin

- preferred

 

2.  Extended curettage

- indicated in spine

- recurrence not uncommon, & difficult to treat

 

3.  Radiofrequency ablation

 

 

Osteochondroma

DefinitionOsteochondroma Hip

 

Outgrowth of benign cartilage from bone

 

Epidemiology

 

50% of benign bone tumours

- single lesion in 90% 

 

Aetiology

 

1.  Multiple

 

Tumour suppressor gene

- family of tumour suppressor genes involved

- have been identified in chondrosarcomas

- 2 hit model of tumourigenesis

 

Both alleles must be mutated for an osteochondroma to form

- if inherit an abnormal allele need other allele to undergo mutation to form osteochondroma

 

2.  Single

 

? Secondary to injury of growth plate

- defect in Perichondral Ring La Croix

- results from herniation & separation of fragment of physis through the periosteal bone cuff 

 

NHx

 

Grows by endochondral ossification of enlarging cartilage cap

- stops at maturity

 

Malignant Transformation

 

Low-grade Chondrosarcoma

- isolated lesion < 1% 

- more common with central lesions

 

Suspicious features (6)

1.  Growth after maturity

2.  Hot bone scan (can be from overlying bursa)

3.  Increased thickness of cartilage cap on CT

- > 1-3 cm (Enneking) 

4.  Pain

5.  Pathological fracture

6.  Disappearance of calcification

 

Enneking

- when the rim of cartilage in an adult exceeds 25 millimeters, it is highly suggestive of malignant transformation

 

Location

 

Any bone formed by endochondral ossification

Arises from cortex of long bone adjacent to physis

 

Most common 

- around knee 

- proximal humerus

 

Clinical

 

Commonly noticed during adolescent growth spurt

 

Symptoms of mass lesion

- pain & tenderness

- decreaed ROM

- compression of NV structure

 

X-ray

 

Femoral Osteochondroma

 

Protuberant bony lesion

- arising adjacent to physis

- directed away from joint

- cortical bone continuous

- marrow space continuous 

- cartilage cap may be calcified

 

Types

1. Pedunculated / exostosis

2. Sessile

 

CT

 

Cortex and medullary cavity of normal bone contiguous with osteochondroma

 

MRI

 

See cartilage cap

- iso-intense with hyaline cartilage

 

Pathology

 

Gross

- looks like cauliflower

- surface covered with irregular cartilage

- cartilage usually 3-5 mm adults

- 5 - 10 mm children

- bone has cortex & medulla 

 

Histology

- cap resembles disorganised physis

- irregular shaped underlying trabecular bone

- may contain calcified cartilage matrix

 

DDx 

 

Juxtacortical OS / CS

Periosteal Chondroma

Osteoma

 

Management

 

Surgical Indications

 

1. Excise painful mass

2. Tendon / NV impingement 

 

Osteochondroma irritating Pes anserinus

 

3. Restore joint motion

4. Correct deformity

5. Biopsy suspicious lesions

6. Central / pelvis / scapula 

- due to higher malignant transformation rate

 

Osteochondroma Cartilage CapOsteochondroma Excised

 

 

 

 

 

Osteoid Osteoma

Definition

 

Benign, bone-forming neoplasm

- characterized by a small nidus of neoplastic tissue

- surrounded by a wide zone of mature, reactive bone

 

Epidemiology

 

10% of benign bone tumours

Age 5-25

M:F 2:1

 

Aetiology

 

Unknown

- thought may be glomus tumour of bone

 

Pain secondary to prostaglandin production

 

Site

 

Intra-cortical position usually

 

60% femur, tibia

- usually at end of diaphysis 

- cancellous or cortical 

 

Posterior elements spine

 

Clinical

 

Characteristic pain

- intense, unrelenting ~ toothache

- night pain

 

Relief by aspirin / salicylates

- dramatic

- often within 30 minutes of one dose

 

May be worsened by ETOH

 

Scoliosis

 

Joint effusion if juxta-articular

 

NHx

 

Gradual resolution with time

 

X-ray

 

A.  Medullary OO

 

Four Diagnostic Features / 50% show all 4

1.  Sharply round or ovoid

2.  < 1cm

3.  Homogenously dense centre

4. ~ 1mm peripheral radiolucent zone

 

B.  Intra-cortical OO

- area of dense bone

- often fusiform-shaped

- central nidus usually not seen

- mimics stress fracture

 

Bone Scan / SPECT

 

Uptake +++

 

Useful to locate lesion especially in spine

 

CT 

 

Thin slice CT best investigation

- lucent nidus

- surrounding dense bone

 

Osteoid Osteoma CT

 

MRI

 

Pathology

 

Gross

 

Lesion is nidus

- < 1 cm diameter

- cherry red & granular

- dense reactive bone peripherally

 

Histology

 

Osteoid Osteoma Histology Nephron GNU Free Documentation License Version 1.2 httpwww.gnu.org/copyleft/fdl.html

 

Immature trabeculae enveloped by prominent osteoblasts / clasts

 

Lucent zone

- surrounding zone of hyperaemic fibrous tissue

- thin lacelike woven bone seams

- AKA osteoid seams 

- haphazard

- numerous vascular channels & rich nerve fibres 

- osteoblasts & giant cells surround

- no chondroid elements

 

No haemopoietic elements in vascular channels

 

Osteoid surround by vascular fibrous stroma

 

DDx

 

Cortical

- infection

- stress stress fracture

- parosteal OS

- osteoblastoma

 

Medullary

- VINDICATE pneumonic

 

Management

 

Non-operative

 

NHx

 

Can resolve

- ? spontaneously heals 

- takes a long time

- NSAID for pain relief

- doesn't progress to cancer

 

Operative

 

Goal is to remove the nidus

 

1.  En Bloc Excision

 

Gold standard

- ensures all of lesion excised

- weakens bone

- risk of fracture especially with lesion in femur

- need bone graft & protection

- send for intra-operative fresh frozen section to ensure have excised OO

 

2.   "Burr Down" Technique

 

Technique

- intraoperative CT guidance

- direct incision over lesion

- shave cortex off with high speed burr to reactive bone 

- scoop nidus out once hit hypervascular zone & sent for FFS

- burr 2mm zone out

- can leave strong reactive bone behind

 

3.  Percutaneous Guided Reaming

 

CT guided in xray suite

- doesn't produce tissue for histology

 

4.  Radiofrequency Ablation

 

Osteoid Osteoma Radiofrequency Ablation0001Osteoid Osteoma Radiofrequency Ablation0003

 

Technique

- GA

- introduce electrode under CT

- can take tissue for histology

- radiofrequency

- increase temperature for 6 mins to 90o

 

Contraindication

- spine

- risk thermal injury to spinal cord / nerve roots

 

Results

 

Rosenthal et al JBJS Am 1998

- equal rates recurrence (9%)

- no complications

- increased patient satisfaction

- drastically reduced in patient stay

 

 

 

Osteoma

Definition

 

Benign, hamartomatous bone-forming lesion arising from the surface of the affected bone

 

Aetiology

 

Excrescence of dense bone which arises from the surface of bones formed by intra-membranous ossification

 

Epidemiology

 

Age 25-50

 

M=F

 

Site

 

Skull or mandible

- classically

 

Shafts of long bones

- often see posterior femur

- similar location to parosteal OS

 

"flat bones and tibial diaphysis"

 

Pathology

 

Gross

- dome-like outcropping

- dense bone

- covered by a capsule confluent with the periosteum

 

Histology

- heavy trabecular bone

- matures into dense cortical bone 

- over-maturation 

- many small haversian canals

- some canals are obliterated 

 

DDx

 

Parosteal osteosarcoma

Exostosis

 

Prognosis

 

Active stage 2 lesion 

- never goes to 3 or 1

 

Association

 

Gardner's Syndrome

 

Management

 

Intracapsular or marginal excision 

- removing the lesion from the surface of the bone

- negligible risk of recurrence

- wide en bloc excision not necessary

 

 

 

 

 

Malignant Bone Tumours

Chondrosarcoma

Definition 

 

Malignant cartilage producing tumour 

 

Epidemiology

 

20% of primary bone tumours

 

3rd most common

- 1 in 500 000

 

Relatively non-aggressive / usually Grade I

 

Average age 40

 

Male > Females

 

Two Distinct Types

 

1.  Primary Chondrosarcoma

 

Arises de novo

 

2.  Secondary Chondrosarcoma (1/4)

 

Chondrosarcoma variant

- arises in existing cartilage lesion

- age > 40

- most common in osteochondromas / enchondromas

- also FD / UBC / Paget's / Radiation

 

A.  Secondary chondrosarcoma in Osteochondroma

 

< 1% chance per lesion 

 

Malignant features

- growth after skeletal maturity

- pain

- calcification in cartilage cap

- disappearance of previous calcification

- cartilage cap > 1-3 cm

- hot on bone scan

- erasure of smooth outline

 

B.  Secondary chondrosarcoma in Enchondroma 

 

Malignant features

- scalloping (endosteal erosion)

- periosteal reaction

- fluffy calcification

- size > 6-10 cm rarely benign

- malignant rare < 20 years

- solitary < Ollier's / Maffucci's

 

C.  Grade 1/2

 

Intra-osseous cartilage forming tumour with worrisome clinical or radiological changes

- i.e. pain at site of previous painless enchondroma

- expansion / large size / endosteal scalloping

 

Problem

- is a diagnostic and management dilemma for radiologists / pathologists / orthopaedic surgeons

 

Management

- biopsy

- can miss malignant areas / sampling errors

- probably best to excise in entirety via curettage to examine all tissue

- covert to resection if frankly malignant

 

Variants

 

1.  Dedifferentiated 

 

Area of low grade with juxtaposed area of anaplastic sarcomatous component

- very aggressive tumour

- prognosis is poor

- few survivors two years after diagnosis

 

2.  Clear Cell 

 

Epiphyseal lesion in young males 

- end of major long bones

- proximal humerus and distal femur

 

Likely malignant chondroblastoma

- destructive low grade

- slow growing

- metastasis very rare

 

Histology

- many cells with abundant clear vacuoles lying between abundant heavily calcified chondroid material

- DDx renal cell ca / clear cell sarcoma / adenoca

 

Treatment

- wide excision

 

The benign appearance and lack of calcification is often misleading

 

3.  Mesenchymal

 

Rare

- young patient

- often extra-skeletal, ribs and jaw

- ill defined osteolytic lesion

- high metastatic potential

 

10 year survival 30%

 

Characteristic biphasic pattern 

- areas of cartilage or chondroid matrix 

- interspersed with areas of small spindle cells similar to Ewing's in a hemangiopericytoma pattern

 

Treatment

- surgery + chemotherapy

 

Location

 

1. Central

 

Within diaphysis of long bone

 

Lytic lesion with punctate or spotty calcification

- can look like bone island

- 3/4 calcification present on plain film

 

Endosteal scalloping is hallmark of chondrosarcoma

- periosteal reaction often minimal

- soft tissue expansion

- in metaphysis may only see subtle periosteal reaction

- expansion with cortical thickening characteristic (20%)

 

Chondrosarcoma Proximal Femur Xray0001Chondrosarcoma Proximal Femur Xray0002

 

2. Peripheral / Juxtacortical

 

Rare

 

Faintly visible sparse calcification in soft tissues

- often behind knee

- radiating spicules at right angles to cortex

- > 2.5cm (OS <1.5cm)

 

Usually no medullary involvement

- cortex rarely affected

- Codman's triangle occasionally

 

3. Soft Tissue

 

Chondrosarcoma Soft Tissue

 

Rare

Treat as soft tissue sarcoma

 

Clinical

 

Pain (80%)

- pain in benign cartilage tumour must be assumed to be malignant

 

Mass

Referred pain

Pathological fracture

Incidental finding

 

Site

 

Pelvis most common

Shoulder / Femur

 

X-ray

 

Worrisome features

- central

- large > 5cm 

- cortical / endosteal scalloping

- cortical break through

- soft tissue mass

- periosteal reaction

 

Pathology

 

Gross

 

Pearly white

- cauliflower-like mass

- surrounded by pseudocapsule

 

Histology

 

Lobules of cartilage

 

Matrix may have

- calcium / necrosis / myxoid degeneration

 

Features that suggest malignancy

- pleomorphism

- hypercellularity

- mitotic figures

- double nuclei in single lacunae

- multinucleated giant cells

 

Can be a great diagnostic challenge for MSK pathologist

- DDx between benign active and low grade (grade 1/2)

- especially difficult between enchondroma and low grade central CS

 

Grading

 

Borderline / Grade 1/2

 

Low-Grade / Grade 1

 

Mild cell atypia and mild hypercellularity

- frequent calcificaiton

- mitoses absent / necrosis rare

- occasional bi / trinucleate cell

 

Medium-Grade / Grade 2

 

More cellular

- 1-2 mitoses / high power field

- less calcification

 

High-Grade / Grade 3

 

Marked atypia & mitotic figures

- densely cellular

- many double nuclei

- no calcification

- obviously anaplastic

- must have chondroid

 

Management

 

Principles

 

Treatment is wide resection

 

Highly resistant to chemotherapy & radiotherapy

- rate of DNA synthesis slow

 

Radiotherapy

- only used if inoperable

- high grade lesions with incomplete margins

 

Exceptions

- mesenchymal -> chemo & radiotherapy

- dedifferentiated -> chemotherapy

 

Surgery

 

Hemipelvectomy Chondrosarcoma

 

Prognosis

 

1.  Grade

 

Low / moderate Grade - 90% 5 year survival

 

High Grade - <10% 5 year survival

 

2.  Site

 

Peripheral - 80% 10 year survival

 

Central - 30% 10 year survival

 

Metastasis

 

Incidence 15%

- 40% preceded by local recurrence

- local recurrence 6x risk for metastasis

 

Grade II:   15 - 40% risk metastasis

Grade III:  75% risk metastasis

 

 

Ewings Tumour

Principles

 

Treatment algorithm similar to OS

 

Overall prognosis similar to OS

- 70% long term survival

 

Definition

 

A malignant neoplasm composed of small round cells of uncertain histogenesis

 

Genetics

 

Recent data suggests it is of neuroepithelial derivation

- ? neuroectodermal cells

- mesenchymal stem cell of neural crest origin

 

Translocation 

- T (11, 22) 

- balanced 

 

Ewing's tumour & PNET have a similar histogenesis

 

Location

 

Central 

- pelvis (12%)

- scapula

- vertebrae

- rib

- sacrum

 

Peripheral 

- femur (20%)

- humerus (11%)

- fibula

 

Epidemiology

 

Usually 2nd decade

- 5-30 years

- peak 10 years

 

M:F 3:2

 

History

 

Usually complain of pain & then swelling

 

± Systemic symptoms

- fever, weight loss, malaise

- poor prognosis

 

Examination

 

Usually large soft tissue mass

 

May have local signs

- tenderness

- erythema & induration

 

Xray 

 

Diffuse permeative destruction

 

Ewings Tumour AcromionEwings Tumour Proximal Femur

 

Extension into soft tissue

 

Periosteal reaction

- codman's triangle

- onion skinning

- sunburst appearance

 

DDx on x-ray

 

Ewing's

Osteomyelitis

EG

 

Blood Tests

 

Elevated ESR & LDH 

- poor prognosis

 

May have anaemia or leucocytosis

 

Lung CT 

 

Pulmonary metastasis (20% GIII)

 

MRI 

 

Shows intramedullary extent 

- extraosseous extent more difficult

- reactive oedema difficult to distinguish from tumour

 

MRI Ewings Sarcoma Proximal FemurMRI Ewings Tumour Proximal Femur

 

Bone Scan

 

Shows occult bone metastases

- 10% have multiple bone involvement at time of presentation

 

Ewings Bone Scan

 

Bone marrow aspirate

 

Important part of staging for Ewing's

 

Staging

 

Usually Grade IIB lesion 

- high grade & extracompartmental

 

20% Grade III

- pulmonary mets

 

In reality all have micrometastasis

 

Bone marrow aspirate and trephine

- at distant site 

- look for marrow spread

 

Histology

 

Sheets of uniform round cells / small round cell tumours

- cells have distinct nuclei with minimal cytoplasm

- indistinct cytoplasmic border

- mitotic activity seldom high

 

Areas of necrosis

- 'geographic necrosis'

- pseudorosettes of cells around central necrosis

 

DDx

 

Use histology, immunohistochemistry, EM and cytogenetics 

- Ewings

- PNET

- lymphoma

- rhabdomyosarcoma

- metastatic neuroblastoma

 

1.  Ewings

 

PAS reaction positive 90%

- stains glycogen and mucin

- other tumours can be positive i.e. neuroblastoma

 

Ewing / PNET

- positive to vimentin / S100 / MIC 2

- MIC 2 specific for neuroectodermal tumours 

 

Cytogenetics

- 11:22 translocation in all  PNET 

 

2.  PNET (Primitive Neuroectodermal Tumour)

 

Variant of Ewing's

 

Composed of

- adult neuroblastoma

- Ewing-like tumour

- Askin tumour - thoracopulmonary PNET

 

Separate group because older age group with worse prognosis

 

3.  Lymphoma of bone 

 

Most important

- older age

- more bone formation

- "common leukocyte antigen" positive

 

4.  Rhabdomyosarcoma

 

Actin / desmin / myoglobin positive

 

EM

- cytoplasmic filaments

- occasional Z bodies

- prominent IC glycogen storage deposits

 

5.  Metastatic neuroblastoma

- PAS positive

- negative to vimentin, MIC 2

 

Other

- small cell OS

- mesenchymal cell chondrosarcoma

- osteomyelitis 

- Eosinophilic Granuloma

 

Management

 

Historically

 

Irradiation only 

- poor results

- survival 25% at 5 years

- local recurrence 35%

- high complication rate (soft tissue damage / pathological fracture / premature closure of physes / 2° sarcoma)

 

Now

 

Chemotherapy is mainstay & primary treatment

- surgery / radiotherapy adjuvant treatment

- significantly more successful

- 60% survival at 5 years

- 40% if metastasis on diagnosis

 

Algorithm

 

1. Neoadjuvent chemotherapy

 

2. Restage

 

3. Surgical resection

- if can get adequate margins

 

4. Chemotherapy

 

5.  Radiotherapy

- if margins inadequate

 

1.  Neoadjuvant Multidrug Chemotherapy

 

Usually dramatically shrinks tumour

- entire soft tissue component can resolve

- period controversial

- principle is to treat to maximum response

 

Pre - chemothearpy

- LFT's / Renal function / Cardiac echo or Thallium scan prior to intensive chemotherapy

- preserve sperm / ovum

 

VAAC Regime

- Vincristine

- Actinomycin

- Adriamycin

- Cisplatin

 

Alternate with

- Iphosphamide

- VP 16 = Etoposide

 

2.  Restage radiographically

 

See response following neoadjuvent chemotherapy

- MRI of affected region

- CT Chest

 

3. Wide Resection ± DXRT of residual tumour

 

Excision best if possible

- amputate if limb salvage not possible

- irradiation if resection not feasible

- resect bone to pre-chemo margin 

- resect ST to post-chemo margin

 

Assess histological response

- > 95% necrosis

 

Surgery improves survival

- removes remaining cancer cells

- removes chemo resistant cells 

 

4. Adjuvant Chemotherapy

 

Continue neoadjuvant regimen

- total chemotherapy is usually 18/12

 

Prognosis

 

1.  Site

- hands and feet better than pelvis and central

 

2.  Size

- > 8-10 cm do worse

- > 100 ml on CT

 

3.  Metastasis at diagnosis

 

4.  Response to chemotherapy

- > 95% necrosis

 

5.  Surgery

- improves survival if resectable

 

Survival

 

No metastasis at diagnosis

- 60% 5 year

 

Metastasis at diagnosis

- 40% 5 year

 

Local recurrence

- 5% local recurrence with surgery

- 25% without

 

Radiotherapy

 

Indications

- incomplete surgical margins

- unresectable

 

If need to use RTX, should use prosthesis rather than allograft

 

Complications

- physeal arrest

- joint contractures

- muscle atrophy

- pathological fracture

 

Secondary malignancy / sarcoma

- increased with young age

- 40x increase if >60 Gy

- strong cumulative risk at 10 years of 35% secondary malignancy

 

 

 

Juxtacortical Osteosarcoma

Epidemiology

 

Uncommon

- 4% OS

 

Females more common 

- similar to GCT

 

NHx

 

Less aggressive locally

- less metastasis

- size / location & duration of symptoms don't correlate with outcome

 

Arise from cortex of bone / periosteum

- parosteal 

- periosteal

- high grade juxtacortical

 

Parosteal Osteosarcoma

 

Epidemiology

 

Comprise most of the 4%

Older (20-40)

Females

 

NHx

 

Lower grade

 

May dedifferentiate (late) into high grade lesion

 

Location

 

Arises from periosteal surface

- in the soft tissues adjacent to the periosteum 

 

Most common in posteromedial distal femur 

- popliteal Fossa

 

Also tibia & humerus

 

Slow indolent growth with eventual invasion of the underlying bone

 

Clinical

 

Painless block to knee flexion

 

X-ray

 

Parosteal Osteosarcoma XrayParosteal Osteosarcoma Xray Lateral

 

May look like osteochondroma

- large lobulated broad-based lesion

- mature bone arising from cortex

- underlying cortex may be thickened

- 25% invade periosteum

- lesion dense with bony pattern

 

"String Sign"

- wraps around bone with intervening periosteum

- gives well-defined radiolucent line

- thin radiolucent line between lesion & cortex

 

CT / DDx from Osteochondroma

 

1. Parosteal OS 

- attached to cortex growing into ST

- normal cortex intact

 

Parosteal Osteosarcoma CT0001Parosteal Osteosarcoma CT0002

 

2. Osteochondroma

- cortex of bone becomes cortex of osteochondroma

- there is modelling of cortex into the tumour

- medullary canal confluent with Exostosis

- posterior femur rare

 

DDx

 

NB Cortical tumours of posterior femur should be considered malignant

 

Osteochondroma

 

Myositis Ossificans

- more mature in periphery

- "like an agg"

- not attached to bone

 

Classic OS

 

Periosteal Chondroma

 

Osteoma

 

Subperiosteal Haematoma

 

MRI

 

Parosteal Osteosarcoma MRI0001Parosteal Osteosarcoma MRI0002

 

Pathology

 

Low grade

 

Regularly arranged bone

- background of spindle cells & fibrous tissue

- may have cartilage cap

- can encircle bone

 

Management

 

Wide Resection

 

Margins

- 7cm proximal & 5cm distally 

- femur: resect posterior capsule & condyles with lesion

 

Parosteal OS Resection0001Parosteal OS Resection0002

 

Prognosis

 

80% cure with surgery alone

 

Periosteal Osteosarcoma

 

Epidemiology

 

Rare +++

15-25

 

Location

 

Diaphysis of major long bones

- typically anterior proximal tibia

- humerus

 

Periosteal Osteosarcoma Anterior Tibia

 

NHx

 

"Peri is a rare bad boy"

- higher grade

 

Pathology

 

AKA High grade juxtacortical chondroblastic OS

- classically shows cartilage +++ 

- c.f. parosteal OS

 

X-ray

 

Punched out lesion

- calcified mass

- in a saucer shaped defect in the cortex

 

MRI

 

Periosteal Osteosarcoma MRI

 

Management

 

Wide resection with neoadjuvant & adjuvant chemotherapy

- DXRT stop local recurrence

 

Periosteal Osteosarcoma Wide Resection0001Periosteal Osteosarcoma Wide Resection0002

Myeloma

Definition

 

Uncontrolled proliferation of single clone of plasma cells

 

Epidemiology

 

Most common malignant tumour of bone

 

Age 50-60

 

2-3 / 100 000

 

Pathology

 

Highly differentiated B lymphocytes

- associated with abnormality of protein synthesis

 

Usually bone marrow of entire skeleton involved

 

Two Forms

 

1.  Multiple Myeloma 95% 

 

2.  Plasmacytoma 5% 

- solitary bone or soft tissue lesion

- usually axial skeleton

- usually disseminates to MM in 5 - 10 years

 

Location

 

Always spine

 

Common in skull, ribs, sternum and pelvis

 

History

 

Bone pain / fatigue / fever / night sweats

 

Laboratory

 

Normocytic normochromic anaemia

 

Other signs bone marrow depression

- i.e. coagulation defects

- leukopenia

- thrombocytopenia

 

Elevated ESR > 100

 

Bence Jones Proteins in urine 50%

 

Serum & Urine Electrophoresis

- monoclonal antibody band

- most sensitive

 

Hypercalcaemia

Chronic Renal Failure

Elevated Serum Urate / Gout

 

Systemic Problems

 

Anaemia

Coagulation defects

Infection 2° immunological deficit

Hypercalcaemia

Amyloidosis 10%

CRF

Gout

 

X-ray

 

1.  Radiographic hallmark is punched out lytic lesions

- axial and appendical skeleton

- widely disseminated / soap bubble appearance

- no sclerotic reaction

 

Multiple Myeloma Pelvis0001Multiple Myeloma Pelvis0002Myeloma Humerus

 

2.  Diffuse osteopenia

- in 15% to 25% of patients, no discrete lysis occurs

- diffuse osteopenia and osteoporosis are the only skeletal manifestations

 

Multiple Myeloma Diffuse Osteopenia

 

3.  Vertebrae Plana

 

Spine Multiple Myeloma

 

4.  Pathological Fracture

 

5.  Pepper pot skull

 

Bone Scan

 

25% negative

- no malignant or reactive bone formation

 

Skeletal Survery

 

Required if negative bone scan

 

Xray

- skull / spine / humerus / femurs / pelvis / chest & ribs

 

Bone Marrow Biopsy

 

Definitive Diagnosis

 

Histology

 

Plasmocytoma Nephron GNU Free Documentation License Version 1.3

 

Sheets of plasma cells

- clock-faced eccentric nuclei

- perinuclear clear area

- increased rER on EM

- no background stroma

 

Cellular atypia not prognostic

 

May see amyloid

 

Management

 

Plasmacytoma 

 

Diagnostic criteria

 

Single osseous lesion confirmed on histology

Bone marrow aspirate from separate site

- < 10% plasmocytosis

No significant BJ in urine

No Ig abnormality in serum or urine

 

Clinical

 

Tend to be younger and have better prognosis

- usually long bone or vertebrae

- in spine commonly present with rapidly progressive paraplegia

- this is more common in plasmacytoma then multiple myeloma

 

NHx

 

70% of plasmacytoma will progress to multiple myeloma

 

Management

- requires biopsy

- resection of lesion if possible

- aggressive DXRT otherwise

 

Prognosis

 

30% cured by surgical en bloc excision and radiotherapy

 

Multiple Myeloma

 

Management

 

Chemotherapy

- corticosteroid

- alkylating agent - Melphalan / Cyclophosphamide

 

Radiotherapy

 

Surgical stabilisation of pathological fracture

 

Orthopedic Management

1. To confirm diagnosis - biopsy isolated lesion

2. To treat impending or actual pathological fracture

3. Rarely to excise solitary lesions

 

Prognosis

 

Multiple myeloma very aggressive with early death

 

 

Osteosarcoma

Definition

 

Highly malignant spindle cell sarcoma of bone in which the malignant cells produce osteoid

- aggressive

- most High grade (II)

- most extracompartmental (IIB)

 

Exception is Juxtacortical (IA)

 

Epidemiology 

 

Most common malignant primary bone tumour excluding myeloma

 

Bimodal peak

 

1.  Second decade / teenagers

- 75%

 

2.  Elderly / 7th decade

- Paget's

 

In fact very rare to see under 13 years

- if looks like OS in this age group then probably Ewing's

 

M > F 3:2

 

Aetiology

 

Li-Fraumeni syndrome

Retinoblastoma - FHx / p53 Defect

Radiotherapy

Paget's disease

 

Classifications

 

Anatomical

 

Classic Central 

- classic high grade

- rare low grade

 

Juxtacortical

- parosteal

- periosteal

 

Extraskeletal

- Jaw

 

Pathological / Lichenstein's

- see below

 

Aetiological 

 

Secondary

- Paget's

- previous radiotherapy

- OM

- Fibrous Dysplasia

- Chondrosarcomatous dedifferentiation

 

Classic Central Osteosarcoma

 

Location

 

Metaphysis of long bones

- distal femur 35%

- proximal tibia 20%

- proximal humerus 10%

 

Osteosarcoma Proximal Tibial Xray0001Osteosarcoma Proximal Tibial Xray0002

 

Can cross into epiphysis / occasionally in diaphysis

 

Presentation

 

Pain

- often activity related

- likely due to microfracture

- most patients relate onset of pain to some minor trauma

- sometimes at night

 

No systemic symptoms

 

Mean symptom duration is 4/12

- 10% metastasis on presentation

- 1% pathological fracture

 

X-ray

 

Usually diagnostic 

 

Osteosarcoma Distal Femur0001Osteosarcoma Distal Femur0002

 

1.  Metaphyseal - involves medullary canal

 

2.  Permeative cortical destruction

 

3.  New bone formation / osteoid

 

4.  Wide / permeative zone of transition / non geographic

 

5.  Codman's Triangle

- triangular periosteal new bone formation

- at proximal and distal cortical margins

- non specific

- reaction to rapid growth

 

6.  Soft tissue component

 

MRI 

 

Osteosarcoma MRI0001Osteosarcoma MRI0002

 

1.  Determines the marrow extent of tumour

- helpful in determining appropriate resection level

- satellite lesions 

- metastasis within reactive zone

 

2.  Identify skip lesions 

- metastasis outside reactive zone

- sagittal and coronal images of the entire bone

 

3.  Soft tissue component

 

Osteosarcoma Proximal Tibial MRI0001Osteosarcoma Proximal Tibial MRI0002

 

4.  Relationship to NV structures

 

5.  Articular involvement

- usually runs along ACL / PCL

 

CT 

 

Complementary to MRI / very useful in the pelvis

 

Bone Scan

 

1.  Resect with 3-4cm margin from bone scan uptake

- resect skip lesions

 

Osteosarcoma Bone Scan

 

2.  Identifies metastatic disease

 

CT Chest / abdomen

 

10% present with pulmonary metastasis

- lungs most common site

- detect > 3 mm

- if resectable then resect lung metastasis via sternotomy

 

Laboratory

 

ALP & LDH

- can be increased 

- worse prognosis 

 

ESR

- May be mild increase

 

Pathology

 

Gross Pathology

 

Starts with intramedullary focus

- bony with areas of focus & haemorrhage

- skip lesions common 5-20% 

- grows up & down medulla

 

Histology

 

Must see malignant spindle cell stroma producing osteoid

- can be difficult to find osteoid

- therefore adequate sampling is essential

 

Osteosarcoma Nephron GNU Free Documentation License Version 1.3Osteosarcoma High Mag Nephron GNU Free Documentation License Version 1.3

 

Pleomorphic spindle cells 

- hyperchromatic nuclei 

- atypical mitotic figures

 

Can mistake fracture callous or periosteal new bone for that produced by malignant cells

 

Low grade central / parosteal OS

- much less cellular

 

Lichenstein Pathological Classification

 

1.  Osteoblastic (50%)

- prominent osteoid 

- delicate network of eosinophilic matrix with both benign and malignant osteoblasts throughout

 

2.  Chondroblastic 

- prominent cartilage

- still have malignant osteoid 

 

3.  Fibroblastic 

- prominent fibrous tissue

- look like fibrosarcoma

 

4. Telangiectatic 

- worst prognosis

- cystic pools of RBC / Giant cells

- may look completely lytic & expansile on Xray

- often with benign giant cells

- can mistake for ABC or GCT

- however see cellular atypia etc amongst stroma

 

5. Giant Cell Rich Osteosarcoma

- older patients

- similar to MFH

- difficult diagnosis

 

6. Small Cell Osteosarcoma

- similar appearance to Ewings

- responds to chemotherapy like PNET

- nests small cells

 

Management 

 

Prognosis

 

Historically

- amputation 

- 1970's 5 year survival 20%

 

Now

- 70% overall survival

- 90% limb sparing surgery 

 

Algorithm

 

1.  Accurate clinical staging

- local (cross sectional imaging - CT / MRI)

- systemic (bone scan & CT chest / abdomen

- biopsy

2.  Neoadjuvant chemotherapy

3.  Restage

- locally and systemic (MRI / CT Chest)

4.  Wide resection 

5.  Post operative chemotherapy +/- radiotherapy if positive margins

 

Chemotherapy

 

Concept

 

Systemic treatment

- treats micrometastasis

- allows limb salvage

 

Rosen in vivo response dictates outcome

 

Outcome best predicted by response as per Rosen

- some OS have P-Glycoproteins pump

- remove chemo from the cell

 

Grade 1 = no cell death

Grade 2 = Partial <90%

Grade 3 = Necrosis >90%

Grade 4 = Complete necrosis

 

Grade 1 & 2 

- < 50% survival

 

Grade 3 & 4 

- > 75% long term survival in OS and MFH

 

Regimen

 

Neoadjuvant & Adjuvant

 

2 cycles pre-operative MACI

- MTX

- Adriamycin (Doxorubicin)

- Cisplatin

- Ifosphamide

 

Surgery

 

Timing

- usually 3/12 after diagnosis

- usually 2/52 after end neoadjuvant chemotherapy

- post chemotherapy tumour is smaller & tends to have a "rind" that makes resection much easier

 

Goal

- resection with wide margin

- 7cm proximally, 5cm distally

 

Options

 

Amputatation

Limb Salvage Surgery

 

Limb Salvage Surgery

 

80% patients can have limb salvage

 

Contraindications / PIN LEG

 

1. Pathological fracture

2. Infection

3. N/V involvement 

4. Immature skeletal age if LLD >6-8cm

5. Extensive muscle involvement

6. Poor biopsy (instead of Good)

 

Technique

 

1. Resection of tumour & biopsy tract

- major N/V bundle must be free of tumour

- wide resection of affected bone 

- normal muscle cuff in all planes

- biopsy tract removed en bloc

- 5cm margin on MRI

- adjacent joint and capsule should be resected

- extra-articular resection preferred

- articular resection mandatory if effusion present

- use tourniquet --> if site contaminated at histology allows amputation to be performed above tourniquet level

- motor reconstruction by local transfer

 

2. Skeletal reconstruction 

- usually 15-20 cm defect

- endoprothesis / arthrodesis / allograft

 

Osteosarcoma Distal Femur Tumour ProsthesisOsteosarcoma Distal Femur Tumour Prosthesis0001

 

Osteosarcoma Proximal Tibial Resection0001Osteosarcoma Proximal Tibial Resection0002

 

3. Local soft tissue and muscle transfers

- adequate soft tissue cover mandatory

 

Local recurrence post OT 

 

Incidence 12%

- poor outcome

- DXRT to prevent local recurrence if +ve margin

 

Can still treat with an attempt at cure

- resectable disease =< 15 pulmonary metastasis + extremity tumour

- treatment is along similar lines

- neoadjuvent chemo

- tumour resection / amputation + median sternotomy and resection of mets

- aim is to relieve tumour burden

- if unresectable then chemotherapy is more appropriate

 

Prognosis

 

Single most predictive factor is the presence or absence of detectable metastasis at presentation

 

Survival

 

IIB 60% 5 year

III  50% 5 year

 

Significant improvement recently

- improved surgical resection

- early resection of lung metastasis

- improved adjuvant chemotherapy

 

Metastasis - 10 - 20% 5 year

 

Resectable pulmonary metastasis post treatment

- 20 - 40% 5 year 

 

CT Chest Solitary Metastasis

 

Local recurrence

- 5 - 10 % 5 year

 

Basic Principles

 

If survive 2 years probably will survive

- no difference in survival between amputation & limb salvage

- long-term survivors 7% risk of developing second tumour due to treatment

 

Poor Prognostic Signs

 

Age < 10 years

Proximal humerus / central lesion

Poor response to chemotherapy

Tumour size > 15cm

Symptoms < 6/12 = aggressive

Pathological fracture

NV involvement

Pelvis much worse than femur which is worse than tibia

Telangiectatic worst

Secondary OS

 

 

 

 

Metastatic

Adult

Background

Aim 

 

The identification of skeletal metastasis & fixation prior to fracture

 

Incidence

 

50% of new cancer cases have metastasis

- 1% have pathological fracture

- increasing with more aggressive palliative care

 

Reasons to Avoid Pathological Fracture

 

Life expectancy after diagnosis

- 40% at 6/12

 

Non-operative treatment poor

- morbidity

- non-union

 

Improves survival 

- 20%

 

More difficult to manage once fractured

 

Clinical presentations

 

1.  Metastasis with unknown primary / rare

 

2.  Pathological fracture

 

3.  Metastasis with known primary / commonest

 

Indications for OT

 

1.  Life expectancy > 2/12

2.  Tolerate major OT

3.  Stable fixation possible

 

Origin

 

Bone seeking malignancies

- 80% PBL

- prostate, breast, lung

- occult metastasis usually breast & prostate

 

Also Kidney, Thyroid & GIT

- 20%

- remember the hexagon

- with malignant melanoma & lymphoma in centre

 

Site 

 

80% axial 

- earliest

 

20% appendicular 

- usually proximal especially proximal femur +++

 

Mechanism of dissemination

 

1.  Haematogenous 

 

Cells carried on fibrin raft

- multiple steps

- cross many tissue layers

- tissue preference

 

2.  Lymphatic 

- renal cell

- OS

 

3.  Direct 

- rare

 

4.  Iatrogenic

 

Bone Reponse to Tumour 

 

Lytic / Sclerotic / Mixed

 

Purely lytic

- lung 

- kidney

- breast

- thyroid

- GI

- neuroblastoma

 

Lytic Metastasis FemurLytic Metastasis Proximal Femur

 

Mixed 

- breast

- prostate

- lung

- bladder

 

Blastic

- prostate

- breast

- bladder

- GI

- lung (oat cell)

 

Neck of Femur Blastic MetastasisBlastic Metastasis Breast

 

Hip Fracture Metastatic Prostate CaHip Fracture Metastatic Prostate Ca CT

 

Bone Destruction

 

1.  Osteoclast mediated 

- 2° local factors eg TNF

 

2.  Direct destruction 

- via enzymes

 

Pain 

 

75% of metastasis

 

Cause

1.  Stimulated nerve ends by direct invasion of tissue

2.  Periosteal stretching

3.  Fractures

4.  Nerve irritation

 

X-ray

 

Need > 50% bone loss to see

 

Remember to xray entire bone

- especially NOF fracture

- need to bypass all lesions

 

Bone Scan

 

Most sensitive screen

 

Bone Scan Multiple Metastasis

 

False negative ~10% 

- Myeloma / EG / Melanoma / RCC

- overwhelm osteoblasts via Osteoblast Inhibiting Factor

 

 

Management

Mirels Prediction system for Pathological Fracture

 

Clin Orthop 1989 

- 38 patients treated with DXRT without surgery 

- most breast cancer

- developed scoring system

- predicts post DXRT fracture risk in preDXRT long bones

- risk of fracture within 6 months 

- irradiated without fixation

 

Four risk factors

 

                1             2             3

Site:     Upper       Lower      Peritroch

Pain:      Mild          Mod       Functional

Lesion:  Blastic      Mixed        Lytic

Size:     <1/3       1/3-2/3       >2/3

 

Score < 7 irradiate safely

- < 4% chance fracture

 

Example

- large lytic lesion in proximal femur

- will score 9 immediately

 

Metastasis Proximal Femur

 

Scores

8     - 15% chance # post DXRT

9     - 33%

10   - 82%

11   - 96%

12   - 100%

 

Mortality 

 

After pathological fracture

- lung Ca = 100% mortality 6/12

- breast Ca = 50% mortality 6/12

 

Median survival metastatic disease

- 50% survive 6/12

- 30% survive 1 year

- lung 6/12

- breast 18/12

- prostate 24/12 

 

Worse if

- hypercalcemia

- lung mets

- paraplegia 

 

Management

 

Aims

 

1. Appropriate patient selection

 

Need to live longer than time for recovery from the operation (> 2/12)

 

Poor prognosis

- lung

- visceral & bone metastasis

- short interval between diagnosis & metastasis

 

2. Reconstruct so that FWB immediately

 

Overall union rate is 35%

- <15% for lung & myeloma

 

3. Address all involved areas in the bone

 

4. DXRT post-op

- entire femur should be irradiated after reaming

- patients that have DXRT have improved function & lower re-operation rate

 

Metastasis survival predication

 

Prediction of prognosis

- score correlates to prognosis

- six parameters with a total score of 0 to 12

 

Parameters

 

General condition according to Karnofsky's performance status

2 points for 80-100%

1 point for 50-70%

0 points for 10-40%

 

No of °spinal bone mets on scan

2 points for none

1 point for 1-2

0 points for 3+

 

No of vertebral metastasis

2 points for 1

1 point for 2

0 points for 3+

 

Metastasis to the major internal organs including lungs, liver, kidney and brain

2 points for no met

1 point for operable lesion

0 points for inoperable lesion

 

Primary site

2 points for thyroid, breast, prostate & rectum

1 point for kidney & liver, uterus, bladder, gallbladder or unidentified

0 points for lung & stomach

 

Spinal Cord Palsy

2 points for Frankel E

1 point for Frankel C or D

0 points for Frankel A or B

 

Prediction

 

Average period of survival

Score of 9 to 12 > 12 /12 

Score of 6 to 8 - 3 12/ 12

Score of 0 to 5 < 3/12

 

Principles

 

Remember principles are same as normal fracture fixation

- fixation will eventually fail if fracture does not unite

 

Healing is slower than normal bone

- irradiation reduces this even more

- 50Gy >14 days after surgery doesn't produce notable increase of non-union

 

Goal is to obtain union

- avoid fracture during procedure

- preserve soft tissue envelope

- rigid internal fixation

- if large lesion >75% of cortex augment with PMMA

 

Preoperative Issues

 

Pre-op embolize vascular tumours 

- renal cell

 

Nutrition 

- consider hyperalimentation

 

Hypercalcaemia 

- from tumour / fracture / metastasis

- stones, bones, abdo moans (pancreatitis), psychic moans

- treat with bisphosphonates -> inhibit osteoclastic activity

 

High uric acid levels 

- prophylaxis against gout

 

Marrow suppression

- from chemotherapy or mets

- risk infection and excessive blood loss at time of surgery

 

DVT prophylaxis

 

DXRT

 

Post-op DXRT for local control

- start Day 14

- 30 Gy / 3000 Rads in fractionated doses

 

There is a period of transient osteoporosis after DXRT in first 2 weeks

- increased fracture risk by 25-40%

- also increased infection rate

 

Healing

 

Harrington 1986 

 

65-85% metastasis will heal with radiotherapy if no fracture

- almost normal bone structure takes 4-6/12

 

Healing of pathological fracture without fixation very poor

- non-union 65-80%

 

With prophylactic fixation & 2200 rads

- 96% remission rate (of which 26% is permanent)

- 94 % bone healing

- 86% union of pathological fracture with interlocking fixation 

 

Fixation Technique

 

Harrington 1986

- aim to span diseased segment with biomechanically strongest construct

- intramedullary best 

- prosthetic replacement has better results than ORIF

- bone grafts not effective with post-op DXRT

 

PMMA 

 

Excellent

- improved results in both animal & human studies

- increased construct strength / bending strength

- improves hardware fixation to bone / improves screw hold

- better pain relief

- immediate weight bearing

- not effected by DXRT

 

Metastasis with Unknown Primary

Likely Origin / Hexagon / PBBLTKClavicle Metastasis

 

                    Thyroid     Breast      

 

Lung           MM  Lymphoma         Kidney        

 

                    Bowel            Prostate

 

Most common site for "unknown primary" 

- lung 63%

- kidney 10%

 

Most common "known primary"

- breast and prostate

 

Plan 

 

1.  Medical History

- previous malignancy

- symptoms for most likely primaries (above)

- history smoking, coughing up blood

- breast lumps

- blood in urine

- bowel disturbance / blood

- fevers / temps / generally unwell

 

2. Physical exam

- breast in women

- prostate in men

- lymph nodes 

- thyroid in neck

- skin

 

3. Plain X-ray 

- bone involved

- any other bones with pain

- CXR

 

4.  Routine bloods

- FBC ELFT

- ESR / CRP

- TFT

- PSA

- Se electrophoresis / BJ urine

- Ca, PO4, Alk Phos

- LDH

- blood film / suspect leukaemia

 

5. Bone scan

- polyostotic / monostotic

 

Bone Scan Multiple Metastasis

 

6. CT Chest/ Abdo / Pelvis

- lung / bowel / renal

 

CT Chest Lung Cancer

 

7.  Biopsy of most accessible lesion

 

Multiple lesion

- biopsy most accessible

 

If isolated bony lesion

- need to treat as primary bone tumour

- stage locally / MRI

- consult with local orthopaedic oncology unit

- discuss biopsy procedure

 

Bone marrow biopsy

- lymphoma / myeloma

 

Seminal Paper

 

Simon et al JBJS Am 1993

- 40 patients prospective study

- allows identification of 85% 

- lab values non-specific in all cases (myeloma excluded)

- history and examination found primary in 8%

- CXR found 43% of primary

- most important finding was benefit of CT

- 75% of primary diagnosed on CT chest, abdo & pelvis

- biopsy diagnosed 8% and confirmed in 30%

 

 

 

 

Specific Management

Subcapital Femoral Neck Metastasis

 

Femoral Neck Metastasis MRIMetastasis Proximal Femur

 

Fractures

 

Principle

- do very poorly with fixation

- hemiarthroplasty or THR

- stem should be 2.5 cortical diameters beyond any area of weakness

- THR if acetabulum involved

 

Lane JBJS 1980 

- 167 patients post proximal replacement

- median life expect 5.6m

- none had mechanical complications

- all walked

 

Prosthesis

 

THR

 

Proximal femoral prosthesis

- indicated for extensive metastasis

- expensive / high dislocation rate due to loss of abductor mechanism

- hemiarthroplasty better to avoid dislocation

 

Proximal Femoral Replacement

 

Intertrochanteric Metastasis

 

Lesion only

 

Options

- either pin & plate / reconstruction nail

- depends if further lesions in femur

- augment with PMMA

 

Fracture / Very Large Lesion

- calcar replacement prosthesis

 

Intertrochanteric MetastasisIntertrochanteric Met Prosthesis

 

Subtrochanteric Metastasis

 

Subtrochanteric Metastasis FemurSubtrochanteric Metastasis and Nail0001Subtrochanteric Metastasis and Nail0002

 

Management

 

Reconstruction nail preferred

- place distal vent prior to reaming

 

Acetabular Metastasis

 

Harrington classification

 

Type I

- minor cavitary defect

- medial and superior walls intact

- standard cemented cup

 

Type II

- major deficit in medial wall

- rim intact

- wire mesh to contain cement or protrusio ring

 

Acetabular Metastasis Type IIAcetabular Metastasis Antiprotrusio Cage

 

Type III

- massive deficit in lateral wall & superior cortex

 

Metastasis Acetabulum Type III APMetastasis Acetabulum Type III LateralAcetabular Metastasis Steinman Pins

 

A.  Flexible threaded Steinmann pins & protrusio cup

- anterior column inserted antigrade through iliac crest

- posterior column inserted retrograde thru acetabulum while palpating sciatic notch & SIJ thru iliac crest incision

 

B.  Saddle prosthesis

 

Femoral Diaphysis 

 

Metastasis Femoral Shaft0002Metastasis Femoral Shaft0001

 

Management

 

IM Nail

 

Supracondylar Femur 

 

Options

- Screw plate / Blade plate

- retrograde nail  

- modular knee prosthesis

 

Metastasis Distal Femur CTRenal Met EmbolisationMetastasis Distal Femur Plate and PMMA

 

Proximal Humerus 

 

Pathological Fracture HumerusPathological Fracture Humerus Plate

 

Options

- ORIF

- tumour prosthesis

 

RCC

 

Shoulder Renal Cell CarcinomaShoulder RCC EmbolisationShoulder RCC Embolisation 2Shoulder Tumour Prosthesis

 

Humeral shaft 

 

Humeral Shaft Metastasis

 

Operative v Non operative

 

 

 

Surgical Options

- locked IM nail

- PMMA + plate (probably more secure with less pain)

 

Metastasis Humerus Plate PMMA0001Metastasis Humerus Plate PMMA0002

 

Weiss et al JBJS Br 2011

- 63 patients

- 11% reoperation rate

- good return of early function without pain

 

Dijkstra Eur J Surg Oncol 1996

- 38 cases, half IMN, half plate + cement

- higher rates of pain relief with ORIF and cement

 

Proximal tibia

 

ORIF

Paediatric

DDx

 

Leukemia 

Neuroblastoma 

Wilm's    

 

Last two usually occur in < 5 year age group

 

Bone scan is method of choice for screening for metastasis

 

Leukemia

 

Epidemiology

 

Most common form of cancer in children 30%

- ALL 5 x AML

- 3 : 100 000

 

History

 

Suspect in any child complaining of diffuse bone pain

 

Xray

 

Lytic transverse lines in epiphyses

- permeative infiltration of bone with periosteal reaction

- focal destructive lesions

- occasional diffuse sclerosis

 

Diagnosis

 

CBC

Blood smear

Bone marrow aspirate

 

Neuroblastoma

 

Background

 

Tumour of sympathetic nervous system

- arises anywhere in the sympathetic nervous system or adrenal medulla

- 10% primary site not found

- malignant small round cell tumour

 

Usually present with abdominal mass and fever

 

Xray

 

Multiple destructive lytic lesions in any part of the skeleton

- often associated with periosteal new bone

- may be permeative

- skull lesions common

 

Diagnosis

 

Elevated serum / urinary catecholamines and VMA

Bone Marrow Aspirate

 

Wilms Tumour

 

Background

 

Nephroblastoma

- arises in kidneys

- usually occurs in first 5 years of life

 

Associated with hemihypertrophy / Beckwith syndrome

 

Most present with abdominal mass

- may have abdominal pain

 

Diagnosis

 

Abdominal USS / CT

 

Management

 

Nephrectomy / chemotherapy

 

Others

 

Ewings 

Lymphoma

Osteosarcoma

Rhabdomyosarcoma

Retinoblastoma

 

 

Principles

Approach to Primary Bone Tumour

Steps

 

1. Establish a differential

2. Stage locally and systemically

3. Biopsy

4. Definitive Treatment

 

1. Establish a Differential

 

Lytic Lesion Distal Femur0002

 

Lesion detected on X-ray

 

Questions

- what do you think it is?

- is it benign (latent, active, agressive)?

- is it malignant (primary or secondary)?

 

Enneking's four questions

 

1.  Where is the tumour?

 

Flat bone / long bone

Epiphysis / metaphysis / diaphysis

Medullary canal / cortex

Eccentric in bone

 

2.  What is it doing to the bone?

 

Expansion

Cortical erosion / breakthrough

Fracture

Permeative margins

 

Wide / narrow zone of transition

- narrow / can draw edge with a pen / good sign

- wide / infiltrative / bad sign

 

The best indication of the aggressiveness of a tumour is the transition zone or margin that surrounds the bone

 

3.  What is the bone doing to it?

 

Periosteal reaction

- Codman Triangle / Sunburst / Onion Skinning

 

Reactive rim

- Sclerotic = Slow growing

- Ill defined = Fast growing

 

Margin

1.  Moth eaten / permeative / ill defined / wide zone of transition / cortical or cancellous

2.  Well circumscribed / narrow zone of transition / sclerotic rim

 

4.  Are there any clues to its histological diagnosis?

 

Bone formation / Calcification

Soft tissue component

Radiolucent / ground glass

Matrix Osteoid / Chondroid / Myxoid / Collagen

 

DDx Lucent lesions

 

FOGMACHINES

 

Fibrous dysplasia

Osteoid Osteoma / Osteoblastoma / Osteosarcoma

Giant cell tumour

Metastasis / myeloma

ABC

Enchondroma / Chondroblastoma / Chondrosarcoma

Hemangioma / HPTH

Infection / Intraosseous ganglion or lipoma / Infarct

Non Ossifying Fibroma / Neurofibroma

EG

Simple bone cyst / Synovial Proliferation

 

Patient factors

 

Age

- consider primary bone tumour < age 40 

- consider metastasis > age 40

- consider EG < age 10

 

History

 

Malignant pain

- night time, severe, increasing

Trauma

 

Examination

 

Soft tissue mass = Aggressive lesion

 

Inflammation = Infection / Ewing's 

 

Pathology tests

 

Serum electrophoresis / Urine Bence Jones (Multiple Myeloma)

PSA - prostatic cancer

ESR - non specific (increased in infection / Ewing's / MM / lymphoma / metastasis)

ALP - increased in Osteosarcoma & Paget's

Calcium / PTH - think of hyperparathyroidism

 

Other Tests

 

Mammogram / Thyroid Ultrasound - metastasis

CT Chest / abdomen / pelvis - RCC, lung cancer, bowel cancer

 

Old X-rays

 

Consider observation if lesion unchanged from at least 2 years ago

 

2.  Stage Locally and Systemically

 

Purpose 

- accurately define the extent of the disease

- prior to proceeding with biopsy and definitive treatment

 

Local / Cross sectional imaging

 

CT

 

Best for assessing mineralisation & bony details

- benign bone tumours

- violation of cortex

- matrix mineralisation

- shows areas that plain X-ray visualise poorly i.e. Spine / Pelvis

 

MRI

 

Best for assessing soft tissue component

 

Assess

1.  ST tumours

2.  Cortical breakthrough / T2

3.  Soft tissue extension / T2

4.  Marrow involvement / intramedullary spread

- T1 with fat suppression

5.  Relationship to NV bundle / T2

6.  Joint & Epiphyseal involvement

7.  Infection - rim enhancement on gadolinium

 

Advantage

- guides extent of treatment

- > 5cm margin on MRI / wide excision

 

Disadvantage

- may be oversensitive

- oedema vs tumour

 

Distant

 

Bone scan

 

Determines if lesion polyostotic v monostotic

- this aids with differential diagnosis

- will identify metastasis

 

Bone Scan Metastasis

 

False negative / cold scan

- inactive benign tumours

- myeloma / EG / melanoma

 

CT Chest / Abdo / Pelvis

 

Purpose

- identify primary tumour that may have metastasised to bone

- identify liver and lung metastasis

 

Lung Metastasis CT Chest

 

Classify Lesion

 

Benign - no need for biopsy

Uncertain or malignant - need for biopsy

 

3. Biopsy

 

Aim

 

A.  To determine whether benign or malignant

 

B.  To determine specific cell type

 

C.  To determine grade

 

See Principles of Biopsy

 

4. Definitive Treatment

 

See specific tumour articles

Biopsy Anatomical Approach

Region specific approaches

 

Theory

- want to traverse one muscle / one compartment

- keep away from NV bundle

- as a rule perform open biopsy through compartment the tumour is in

- this is the compartment that will require surgical removal in wide excision

- direct approach without going through muscle if possible i.e. tibia, distal ulna

 

Lower Limb

 

Thigh

 

1.  Lateral compartment ST tumour

- lateral approach

- through ITB

- through vastus lateralis / anterior to lateral intermuscular septum

 

2.  Medial compartment ST tumour

- medial approach

- through gracilis

- keep away from NV bundle

 

3.  Posterior compartment ST tumour

- posterior approach / transmuscular

 

Femur

 

1.  Femoral head / neck

- depends if lesion benign or malignant

- tdranstrochanteric: for completely contained osseous tumour

- Watson-Jones: however if is malignant will consign patient to extra-articular resection

 

Proximal Femur Tumour

 

Proximal Femur Bony Tumour0001Proximal Femur Bony Tumour0002

 

2.  Subtrochanteric

- remember lesions here in elderly may be chondrosarcoma from enchondroma

- lateral approach

 

Tumour Subtrochanteric Femur

 

3.  Femoral Shaft

- lateral through vastus lateralis

- anterior cortical window

 

Femoral Shaft Bony Lesion

 

4.  Condyles

- medial or lateral approach

- incision through medial or lateral vastus

 

Bony Lesion Lateral Distal Femur

 

Popliteal fossa

 

Popliteal fossa / parosteal OS

- posterior approach

- go through hamstrings or gastrocnemius

- depending on whether lesion medial or lateral

 

Parosteal Osteosarcoma

 

Patella

 

Direct anterior

 

Patella Lytic Lesion

 

Tibial

 

1.  Medial plateau proximal tibial bony tumour

- direct medial approach directly onto bone

 

Proximal Tibial Lytic Epiphyseal Lesion XrayTibial Shaft Lesion

 

2.  Lateral plateau proximal tibial bony tumour

- through biceps femoris

- avoid CPN

 

3.  Tibial shaft

- through tibialis anterior

 

4.  Medial malleolus

- direct medial approach

 

5.  Posterior distal tibia

- posterolateral approach

 

Fibula

 

1.  Fibular head

- incision posterior fibular head

- expose and protect CPN

 

2.  Fibular shaft

A.  Direct lateral

- straight down to bone

- fibula / peroneals and nerve get taken in salvage

B.  Posterolateral approach

 

3.  Lateral malleolus

- direct lateral approach

 

Distal Fibular Lucent Lesion

 

Leg

 

1.  Proximal posterior compartment ST tumour

- medial to tibia

- preserve anterolateral compartment

 

2.  Proximal anterolateral compartment ST tumour

- direct approach through tibialis anterior

- will likely not be able to preserve CPN

 

Talus

 

1.  Head and neck

- medial approach between T anterior and T posterior

- may need medial malleolar osteotomy

 

2.  Body

- Ollier's approach

 

Calcaneum

 

Bony tumour

- direct lateral

- avoid medial NV bundles

 

Calcaneal Bony Lesion CTCalcaneal Bony Lesion MRI

 

Foot

 

1.  Navicular / Medial cuneiform

- direct medial

 

2.  Cuboid

- direct lateral

 

3.  Intermediate cuneiform

- between EHL and EDC but away from dorsalis pedis

 

4.  Lateral cuneiform

- lateral to EDC

 

5.  Metatarsals / phalangeals

- dorsal approach

 

Metatarsal tumour

 

6.  Soft tissue tumour

- medial or lateral as required

 

Soft tissue sarcoma medial foot

 

Pelvis

 

Iliac crest

- definitive surgery via ilioinguinal approach

- best to use iliac crest aspect of this approach

- can go medial or lateral to crest

 

Pelvis Soft Tissue Sarcoma

 

Anterior column

- Watson - Jones through G medius

- avoid femoral NV bundle

 

Posterior column

- Kocher - Lagenbeck through G maximus

 

Pubis

- Pfannenstiel approach

 

Ischium

- lithotomy position

- detach adductor and hamstrings

 

Sacrum

 

Direct posterior approach

 

Upper Limb

 

Humerus

 

1.  Proximal humeral bony tumour

- direct lateral

- through deltoid muscle

- never deltopectoral (condemns patient to forequarter amputation)

 

2.  Shaft

- modified Henry

 

3.  Distal humerus bony tumour

- lateral longitudinal to capitellum

- medial approach to trochlea

 

Radius

 

1.  Proximal bony tumour

- protect radial nerve at all times

 

A.   Radial head: Kocher approach / through anconeus

B.   Proximal third:  Henry approach / take off supinator

C.   Middle third: Henry approach / take off pronator teres

D.   Distal third: Henry approach / take off pronator quadratus

 

2.  Distal radius

- dorsal approach as salvage is always wrist fusion

- through second compartment / sacrificeable

 

Lesion distal radius

 

Wrist / Hand

 

1.  Carpus

- dorsal approach

 

2.  Metacarpal / phalanges

- dorsal approach

- avoid volar to preserve NV bundle

 

Sarcoma Finger

 

Ulna

 

1.  Proximal ulna bony tumour

- direct subcutaneous approach

- away from ulna nerve

 

2.  Coronoid

- posterior approach with window for biopsy

 

3.  Distal ulna bony tumour

- direct lateral approach between FCU and ECU

- down onto subcutaneous surface of ulna

 

Clavicle

 

Clavicle

- direct subcutaneous

 

Scapula

 

Acromion - deltoid split

Spine - transverse approach

Body - Judet posterior approach

Glenoid - posterior approach, through T major

Coracoid - deltopectoral approach

 

Spine

 

C1-2 bony tumour

- anterior retropharyngeal approach

- anterior to SCM

- resect submandibular gland and ligate duct

- CN XII superiorly

- between carotid sheath and larynx

- biopsy through longus colli

 

C3-T1

- Smith-Robinson approach

- vertical incision

- split longus colli

 

T2 - T12

- posterior approach and transpedicular

- open or CT guided

 

L1-L5

- anterior retroperitoneal approach

 

 

 

Chemotherapy

Sensitivity

 

High grade tumours often sensitive to intensive chemotherapy

- OS

- Ewings

- MFH

 

Low grade often insensitive 

- Chondrosarcoma

- Parosteal OS 

 

Role

 

1.  Eradication of overt & micrometastasis

- OS 80% have micrometastasis

 

2.  Reduce tumour locally 

- makes limb salvage easier

 

3.  Improve local control

- lesser role

- local control has no real impact on survival

 

Mode of Action

 

Interferes with synthesis of

- DNA

- RNA

- Protein

 

Action

 

Non-specific

- all cells

 

Cell Cycle-specific

- proliferating cells

 

Cell Phase-specific

- portion of proliferating cells

 

Types

 

1. Alkylating agents

- Cyclophosphomide

- Cisplatin

- Ifosfomide

 

2. Antitumoural Antibiotics

- Doxorubicin

- Bleomycin

 

3. Plant Alkaloids

- Vincristine

- Vinblastine

- VP-16 (Etoposide)

- Taxol

 

4. Antimetabolites

- Purine and Pyrimidine Antagonists

- Thioguanine & Mercaptopurine

- Cytarabine & 5-FU

- Methotrexate - Folate antagonist

 

Supportive therapy

 

Responsible for much of improvements in results

 

G-CSF 

- 175 amino acid glycopn 

- developed from E.coli recombinant DNA technology

- improves recovery by reducing neutropenic period

- neutropenia can be devastating in the more aggressive protocols

- G-CSF allows the dose to be increased further and achieve higher cell kill

 

Blood Products

- when needed 

- i.e. platelets

 

N 5-formyl-tetrahydrofolate

- MTX rescue

- following very high doses

 

Leucovarin 

- MTX rescue

 

Ondansetron 

- serotonin antagonist

 

Osteosarcoma Protocol

 

MACI pre op + G-CSF support

 

MTX

- high dose

- can see dramatic response

- blocks conversion folate ->tetrahydrofolate

- can cause renal failure

- alkylate urine and hydrate +++

- leucovorin rescue

- otherwise die very quickly

- doesn't suppress bone marrow to any great degree so use after an alkylating agent

- side effects related to levels

- mucositis and ulcers / pleuritis / conjunctivitis / hepatic and renal failure

 

Adriamycin

 

Cisplatin  

- standard drug for OS

- alkylating agent 

- direct DNA damage

- SE - emesis, renal and ototoxic

 

Ifosfamide

- new generation alkylating agent

- single most effective agent against sarcoma

- activated by hepatic P450 system

 

Timing

 

Adjuvant (Postoperative)

 

Neoadjuvant (Preoperative)

 

Standard strategy is neoadjuvant

- allows assessment of response early in disease

- restaging investigations after neoadjuvant chemotherapy

- imaging, histology

 

Advantage

- improves limb salvage

- allows planning of surgery

- re-stage after chemo

- prognostic

 

Efficacy 

 

Measured by extent of tumour necrosis

- good response is > 90% necrosis

- poor response is < 90% necrosis

- response is best prognostic factor

 

Rosen in vivo response dictates outcome

- Grade 1 = no cell death

- Grade 2 = partial <90%

- Grade 3 = necrosis >90%

- Grade 4 = complete necrosis

 

1 & 2 < 50% survival

3 & 4 > 75% long term survival in OS and MFH

 

Using Cisplatin, Doxorubicin, MTX

 

Resistance 

 

Tumour cells develop cell membrane pumps to expel chemotherapy

 

Side-Effects

 

A.  Proliferating tissues

 

Most commonly

- bone marrrow

- oral & GIT epithelium

 

Effects are

- myelosuppression

- stomatitis

- mucositis

- N & V

- anorexia

- infertility

- hair loss

 

All males store semen prior to chemotherapy

Females consider egg retrieval

 

B.  Non-Proliferating Tissues

 

Less predictable effects

 

1.  Pneumonitis & Pulmonary fibrosis 2° Bleomycin

(blasts the lungs)

 

2.  Cystitis 2° Cyclophosphamide

(cills the kidneys)

 

3.  Nephrotoxicity 2° MTX & Cisplatin

 

4.  Cardiotoxicity 2° Doxorubicin

(death to the heart)

 

5.  Neurotoxicity 2° Cisplatin & Vincristine

 

Adverse effects on Surgery

 

Systemic

- neutropenia

- thrombocytopenia

- coagulopathy

 

Local

- cytotoxicity to tissue

- wound complications

- delayed bone healing

 

Results

 

Osteosarcoma

 

Improved 5 year survival from 20 - 80%

- improved ability limb salvage OT

- multi-agent treatment

- Rosen T10 protocol (MAC CAB)

- Methotrexate / Adriamycin / Cyclophosphamide / Cis-Platin / Actinomycin-D / Bleomycin

 

Pre-operatively

- 2 / 12 months

- 3 cycles 2 weeks apart

 

Restage disease

- repeat MRI

- may repeat CT Chest / Abdo & bone scan

 

Surgery

 

Post-operatively

- regimen continued for further 6-12/12

 

Ewing's Sarcoma

 

Previous treatment was surgery or radiotherapy

- dismal outlook

- < 15% 5 year survival

 

Combination with chemotherapy gives much better results

- 50% 5 year disease-free survival

- 70% 5 year overall survival

- 30% 5 year if present with metastasis

 

Multiagent neoadjuvant chemotherapy

- 3/52

- Vincristine / Actinomycin D / Cyclophosphamide / Adriamycin

- alternating with 3/52 of Iphosphamide / VP-16

 

Surgery performed when estimated that maximal response achieved

- usually at 3-4 /12

 

Malignant Fibrous Histiocytoma

 

Mainstay of treatment is resection

- multiagent neoadjuvant chemotherapy improves 5 year survival from 50% - 75%

 

Chondrosarcoma

 

Primary treatment is surgery as tumour resistant to chemotherapy

- occasionally used for palliation but effects unclear

- hormonal agents may be effective

- i.e. HGH, somatomedin

 

Childhood Rhabdomyosarcoma

 

Improved survival from 20% to 60% 5 year

- much poorer for metastatic disease

 

Adult Soft Tissue Sarcomas

 

Treat as one disease

- controversial

- no clear evidence of long-term efficacy with chemotherapy

- exception is MFH and synovial sarcoma

 

 

 

 

Histopathology

Grading Neoplasia

 

Most important

 

Mitotic Figures

Necrosis

 

Next Important

 

Anaplasia

Pleomorphism

Atypia

  

Standard Microscopy

- specimen fixed in formalin

- decalcified if contains bone

- embedded in paraffin

- water replaced with wax

- fine sections cut

- stained with Haematoxylin & Eosin

- Haematoxylin stains Protein blue

- Eosin stains Cytoplasm & Collagen pink

 

Special Stains

 

Van Gieson's

- myogenic tumours

 

Reticulin

- vascular tumours, clear cell sarcoma

- alveolar soft part sarcoma

 

Periodic Acid Shift

- Ewing's/ PNET

- Rhabdomyosarc 

- Neuroblastoma

 

Melanin

- melanoma

 

Masson's Trichrome Stain

- presence of collagen = fibrosarcoma

 

Frozen Section

 

Specimen fresh

- specimen frozen with liquid nitrogen

- fine sections cut

- similarly stained

 

Immunohistochemical Stains

 

Rationale

 

Identifies certain proteins

 

Technique

 

Slide prepared as above

- particular antibody-containing solutions put on slide

- antibody binds with antigen if particular protein present

- then another antibody with attached colouring agent put on slide

- binds to antigen-antibody complex if present

- thus stains if protein of interest present

 

Types IHC Stains

 

Keratin + / Vimentin -

- carcinoma

 

Keratin - / vimentin +

- sarcoma

 

Keratin + / Vimentin +

- synovial / epitheloid sarcoma

- adamantinoma

- osteofibrous dysplasia

- chordoma

 

S100 

- Melanoma

- Schwann / Neural cells

- Ewings / PNET

 

Factor VIII

- vascular tumour

 

MIC2

- Ewing's, PNET

 

Actin

- muscle, myofibroblasts

 

Desmin

- muscle

 

Myoglobin

- skeletal muscle only

 

LCA (leucocyte common antigen)

- lymphoma

- haemopoietic lesions

 

Cytokeratin

- skin

- synovial sarcoma

- epithelioid sarcoma

 

Epithelial Membrane Antigen

- synovial sarcoma

- epithelioid sarcoma

 

NSE, GFAP, Neurofilament PR 

- round cell tumours

 

DNA Ploidy

 

Measure DNA content in each cell by flow cytometry

- quantify no cell with normal & abnormal amounts DNA

- N = 23 pairs (Diploid) or 46 total 

 

Little benefit as

1. Not used to grade neoplasia

2. Not useful for prognosis

3. Can't diagnose tumour type

 

Cytogenetics

 

Rationale

- certain tumours have identified genetic abnormalities

 

Technique

- cells cultured

- halted in metaphase

- karyotyping performed

- chromosomal banding patterns identified

 

Examples

 

Ewings / PNET

- t (11, 22)

- EWS - FLI

 

Clear Cell Sarcoma t (12, 22)

 

Synovial Sarcoma t(X, 18)

 

Liposarcoma

Rhabdomyosarcoma

Infantile Fibrosarcoma

Trisomy 11, 17, 20

 

Electron Microscopy

 

Rationale

 

Certain ultrastructural features differentiate tumour types

 

DDx PNET/ Ewing's / Neuroblastoma

 

Epithelial structures in carcinoma

 

Sarcomeres in Myosarcoma

 

Melanosomes in Melanoma

 

 

 

Principles of Biopsy

Aims

 

1.  Provide representative sample

- to determine whether benign or malignant

- to determine cell line

- to grade lesion

 

2.  Not compromise definitive treatment

 

Timing

 

Last step in evaluation / after staging

 

Don't perform definitive procedure immediately after biopsy unless

- pre-operative & Xray information characteristic

- fresh frozen section unquestionably confirms diagnosis

- i.e. ABC, GCT

 

Usually biopsy, then definitive OT later

 

Open vs Closed

 

Overall, open preferred

 

Open

 

Advantage

- more tissue

- lower sampling error

 

Disadvantage

- larger field to excise later

- higher local complications (i.e. infection, haematoma)

 

Needle Biopsy

 

Advantage

- less expensive / less risky

- smaller field to excise later

 

Disadvantage

- reduced accuracy 70-85% vs 95% with open

 

Indications

1.  Homogenous tissue expected - Myeloma

2.  Treatment unchanged by subtle differences - Soft Tissue Sarcoma

3.  Diagnosis relatively certain - Metastasis

4.  Access difficult - Spine, Pelvis

5.  Expert histologist available

6.  Patient not able to tolerate big surgery or GA

 

Complications biopsy tract

- wound contamination -> tumour recurrence

- wound dehiscence

- infection

- haematoma - always drain biopsies (haematoma spreads tumour)

 

Performed by treating surgeon at treatment centre

 

Results

 

Mankin 1982 JBJS 

- complication rate x 5~12  when performed by other surgeon / other hospital

- 60% major error in diagnosis

- 20% treatment compromised by biopsy

 

Mankin and Simon 1996

- musculoskeletal tumour society

- follow-up study from 1982

- results no different from previous study

- 597 patients 21 institutions

- rate of diagnostic error 17.8%

- problems with biopsy causing change in treatment to more difficult or complex procedure 19.3%

- change in outcome attributed to biopsy 10.1%

- 18 patients had unnecessary amputation

- errors, complications and changes in course and outcome

- 2 - 12x more common than if biopsy done in referring institute instead of treatment centre

- 19.3% of biopsies planned poorly

 

Most common errors

 

Transverse incisions in soft tissue tumours

Needle biopsies only 60% accurate compared to 76% with open biopsy 

 

Conclusion

 

Not always possible to perform biopsy in treatment centre

- do so after review of case and imaging with tumour surgeon

- discuss optimum biopsy approach

 

Biopsy Technique

 

Pre-operative

 

Tumour staging first / all imaging obtained

Images reviewed with experienced MSK radiologist

Treating surgeon does biopsy at treating hospital

- discussed with tumour centre if not possible

Ensure expert pathological facilities

- experienced MSK pathologist

- frozen section available

No pre-op antibiotics / infection always in DDx

Tourniquet

- no exsanguination

- release before closure and obtain hemostasis

 

Intra-operative

 

1.  Approach

- plan with future OT in mind

- all aspects of biopsy tract must be excised later

- incision must be incorporated in definitive surgery

- violate one compartment only / trans-muscular

- incision is longitudinal, no undermining skin edges

- don't expose NV structures

- meticulous haemostasis

 

2.  Biopsy

- round cortical windows / decreased stress-risers

- swab taken / tissue for M/C/S

- tissue for FFS / histology

- no closure until discussion with pathologist on phone

- ensure they have enough to make a definitive diagnosis / cell line / grade 

 

3.  Closure

- plug bone windows with PMMA / minimises tumour spread 

- achieve haemostasis

- closure in layers

- drain exit site in line with and through wound

- subcuticular suture to skin

- firm dressing

- immobilise 

 

Post operative

 

Very careful post op

- pathological fracture changes outcome

 

Team approach

- pathologist / radiologist / oncologists / radiation oncologist

- all results are reviewed to ensure correct diagnosis and management

 

Radiotherapy

Definition

 

Use of ionising radiation to damage DNA to prevent cell replication

 

Mechanism

 

Most rapidly replicating cells affected the most

 

Radiosensitive tissue

- high turnover tissue

- high blood supply

 

Give DXRT in incremental radiation

 

Produce free radical by breakup of H2O

- H2O -> H+ + OH-

- free radicals denature DNA

- damage DNA so that cell can't divide 

- cell then dies without dividing

 

Particles 

- bigger particle produces greater damage

- different particles have different RBE (Radiobiological effectiveness)

- each particle works the same way- free radical production

 

Both tumour & normal cells injured

- normal cells recover

- tumour dies

 

Need O2 for DXRT to work

- hyperbaric better

- unoperated bed better

 

Types

 

1.  Photons

 

2.  Gamma Rays 

 

Go through body / not absorbed as particles

- Cobolt 60 - Almost obsolete

- Iridium - Occasionally used in Brachytherapy

- Caesium - Used for Gynaecology tumours

- Radium - Now obsolete

 

3.  X-Rays 

- diagnostic 50-150 kv

- deep X-Ray Therapy - 300 kv

- linear accelerators - 4-24 mv

 

4. Particle beams

 

Electrons - Linear Accelerators

- particle beams via linear accelerator

- produce electron beams -> absorbed as particles

- depending on energy of beam can dial up depth of beam 

- 6MeV - 20MeV 

 

5.  Beta - Rays

- electrons given off by ionised substance

- injected locally

- Strontium, Yttrium & Samarium

 

6.  Neutron beams 

- very damaging

- experimentally are producing heavy particle beams via cyclotrons as neutron beams

 

Technique

 

Fractionation

- 1 large dose vs 60 small doses

- curative / fractionation

- palliative / minimal fractionation

 

100 Centigray = 100 Rad = 1 Gy

 

Metastasis

- 1000 Centigray in 10 doses

 

Bone Tumour

- 6000 Centigray in 30 doses

 

Curative

 

Maximum possible dose with acceptable damage to normal tissue

- 60 Gy in 30 fractions over 6/52

- equivalent to 18 Gy in one dose

- fractionation decreases late effects on normal tissue

- increased differential between tumour & tissue damage

- allows repair between treament

 

Usually given 3/52 postoperatively

- allows wound healing

- minimum delay as tumour interference activates cells in arrest phase

 

Careful planning

- multiple fields

- minimum normal tissue damage

 

Palliative

 

Short course with lower total dose

- 30 Gy in 10 fractions

- 3 CentiGy or 3 Rad or 0.03 mRad

 

Simple field set ups

- late morbidity less of an issue

- delays callus formation if pathogical fracture

- slows chondroid formation at fracture but not with osteogenesis 

- 96% local remission

 

Method of Delivery

 

External Beam

 

Brachytherapy

- old method

- place radioactive agent down tube 

- high risk to doctor giving treatment

- now use remote brachytherapy

 

Intrapoerative radiotherapy

- give dose to site at time of surgery

- give high dose with minimal local effects

 

Remote Afterloading

- pour radio-active agent down into tube

 

Timing 

 

6 Week Rule

- start radiotherapy < 6/52 after OT

 

Preoperative

- better blood supply 

- needs oxygen to effect cell kill

- shrinks tissue from neurovascular bundle

- may allow limb salvage

 

Disadvantage

- impairs healing

 

Postoperative

- usually preferred

- wait for wound to heal

- start within 6/52 otherwise repopulates with tumour cells

- also easier to identify site of tumour

 

Morbidity

 

100% side effects

 

Early 

 

Erythema / Dry desquamation / Ulceration skin

Lymphopaenia

Telangectasia

 

Myelosuppresion

 

GIT effects

 

Late

 

Skin Fibrosis

Joint Contracture

Muscle Atrophy

Lymphoedema

Hair loss

 

Chronic bone changes / fracture

 

Post Radiotherapy Changes With Stress Fracture

 

Osteoradionecrosis - eg AVN Femoral head

 

Transverse myelitis

 

Lung fibrosis

 

ST & bony hypoplasia in kids

- physeal arrest

 

Endocrine suppression

 

Infertility 

 

Skin cancers

 

Sarcomatous change

 

Specific tumours

 

Osteosarcoma

 

No indication for preoperative treatment

 

May be used for

- unresectable 

- palliation for metastasis

 

Ewing's Sarcoma

 

Very high radioresponsiveness 

- but low curability

- effective if combined with chemotherapy

- surgery & chemotherapy  have better results

 

Chondrosarcoma

 

Relatively radioresistant

 

May be used for

- recurrence

- inoperable disease

 

Myeloma

 

Effective for Plasmocytoma

Combined with chemotherapy for Multiple Myeloma

 

Soft Tissue Sarcomas

 

Indications

- doubt about surgical margins

- NV structures close to tumour

- 50 Gy DXRT  preoperatively

- 10 Gy Brachytherapy postoperatively

 

Useful to give radiotherapy preoperatively for sarcomas

- because it develops a rind around the tumour 

- makes it a lot easier to excise

- operate at about 6 weeks post radiotherapy

 

 

Staging

Musculoskeletal Tumour Society Staging System

 

Stage 1  Benign inactive

Stage 2 Benign active

Stage 3  Benign aggressive

 

Stage I Low grade malignant

Stage II  High grade malignant

Stage III  Metastases to any site

 

Purpose

- guide prognosis

- guide surgical management

- guide adjunctive therapies

 

Compartments

 

Definition

 

A compartment is an anatomically confining space

- will resist tumour spread beyond its boundaries 

 

Intra-compartmental (4)

- intra-osseous

- intra fascial compartments

- superficial to deep fascia 

- par-osseous

 

Extra-compartmental 

- extension beyond above

- pelvis

- popliteal fossa

- axilla

- cubital fossa

 

Benign

 

Latent / Inactive

 

Non-ossifying fibroma

- benign, intracapsular, no metastatic potential

- typical clinical course is unchanging or self-limiting

- tendency to self healing

 

Active

 

ABC

- characteristic is progressive growth

- benign, intracapsular, no metastatic

- X-ray and clinical appearance suggests active but contained growth

- without extracapsular penetration

 

5-10% local recurrence with curettage 

- respond well to wide excision

 

Aggressive 

 

GCT

- locally aggressive but no metastatic potential

- benign, extracapsular but intra-compartmental

- X-ray and clinically characterised by extracapsular penetration & destructive growth

 

10-20% recurrence after marginal excision 

- may even recur after wide excision

- best treatment by excision with cuff of tissue

 

Malignant

 

1A Low Grade Intra-compartmental

1B Low Grade Extra-compartmental

 

2A High Grade Intra-compartmental

2B High Grade Extra-compartmental

 

3 Metastasis

 

Low grade

- low metastatic potential

- parosteal OS

 

Treatment is surgery alone

- don't require systemic treatment

- tumour nodules in reactive zone but not beyond

- wide excision

 

High grade

- grow rapidly & metastasise early

- tumour nodules beyond reactive zone

- classis central OS

 

Treatment is surgery & systemic treatment

 

 

 

Tumour Surgery

Aim

 

Tumour removal to gain local control & minimize recurrence while maintaining functional limb 

 

Margins

 

1.  Intralesional

 

Within lesion

- macroscopic tumour remains

 

2.  Marginal

 

Within reactive zone

- microscopic tumour remains

 

3.  Wide 

 

Intra-compartment and outside of reactive zone

- tumour & cuff of normal tissue

 

Beyond reactive zone

- > 7cm level on Te99 scan

- > 5cm level on MRI

- may leave skip lesions behind

- hence MRI

- remove biopsy site

- may mean amputation

 

4.  Radical

 

Extra-compartmental 

- removal of all compartments that contain tumour

 

Amputation is not necessarily Radical

- radical resection possible with limb salvage 

 

Exceptions

 

Skin & subcutaneous tissue

- wide margin is < 5 cm

- radical margin is > 5 cm

 

Extracompartmental lesions

- can't have radical exision of extracompartmental lesions

- no longidudinal barriers to extracompartmental spaces

 

Two compartments

- both compartments must be removed to achieve radical resection

- sometimes only practical way to achieve this is amputation

 

Contamination

- when lesion entered, wound contaminated

- if exposed tissues not removed, margin is intracapsular

 

Surgery & Recurrence rate

 

  IA IB IIA IIB
Intralesional 90% 90% 100% 100%
Marginal 70% 70% 90% 90%
Wide 10% 30% 50% 70%
Radical 0% 0% 10% 20%

 

Limb Salvage

 

About 80 - 85% patients with OS, Ewing's, CS amenable to limb salvage

 

Principles

- must have same survival rates

- must not delay adjuvant treatment

- reconstruction should be enduring with minimal complications

- function should approach that achieved by amputation

 

Contraindications

 

PIN LEG

- pathological fracture

- infection

- NV bundle involvement

- LLD > 8 cm

- extensive muscle loss

- Good v poor biopsy

 

Absolute

 

1.  Can't obtain wide margins

2.   Major NV involvement

- vessel grafts are possible

- nerve remains at risk

3.  Infection

 

Relative

 

1.  Pathological  fracture

- hematoma spreads tumour beyond accurately defined limits

- may necessitate amputate

 

2.  Inappropriate previous biopsy

- contamination of other compartment

 

3.  Significant skeletal immaturity

- predicted LLD > 8cm

- adjustable / growing joint replacements availiable

 

4.  Extensive muscle involvement

- leave leg non functional

 

5.  Medically unfit

 

Technique

 

Radical or wide resection

- extra-articular resection is preferred if a tumour is adjacent to or involves a joint

- prophylactic antibiotics

- no tourniquet if possible

- no eschmarc

- biopsy site excised

- tumour &/or pseudocapsule not visualised during procedure.

- distant flaps should not be developed until the tumour has been removed

- all dead space should be eliminated, & haematoma formation should be prevented

- surgical wound marked with clips for later radiatherapy

- motor reconstruction by regional muscle transfer

- adequate soft tissue cover by flap to avoid skin necrosis

 

Reconstruction Options

 

Arthrodesis

Autograft (remove and irradiate)

Allograft arthrodesis

Allograft arthroplasty

Modular Endoprosthesis

 

Modular Endoprosthesis 

 

Proximal Femoral Replacement

 

Advantage

- early weight bear and rehabilitation

- lower infection rates than allograft

- no risk of non union like allograft

 

Types

- rotating hinge

- expandable if final LLD > 2cm

- modular

 

Contraindications

- < 8 years old

 

Complications

 

Early complications

- wound infection

- skin necrosis

- DVT

- neuropraxia

- instability

 

Late complications

- prosthesis breakage

- LLD 

- lysis

- instability

- late infection

 

Expandable Prostheses

 

Lengthen 2cm every 18 months

- surgical procedure

- excise fibrous tissue to prevent joint stiffness and protect NV bundle

 

Average lengthening 9 cm

 

50% complication rate

 

Massive Allograft 

 

Massive Femoral Allograft0001Massive Femoral Allograft0002

 

Advantage

- biological reconstruction

 

Disadvantage

- incorporation is a slow and incomplete process

- 20% will fail within 5 years

 

Indications

- patient < 20 years old

 

Complications

- infection 11% (sometimes only salvageable by amputation)

- fracture 16% (up to 3 years later)

- joint instability

- non union (increased by chemo/DXRT)

- OA (15% at 10 years with osteochondral allograft)

 

Results

 

Intercalary > osteochondral

 

Intercalary

- 80% good results

- 30% non union at one osteosynthesis site requiring intervention

 

Osteochondral

- 73% good results

 

Allograft - prosthetic

- 77% good results

 

Rotationplasty

 

Concept

- creates a functional BKA

- superior to AKA

 

Advantage

- low complication rate

- very functional

 

Disadvantage

- high rate cosmetic dissatisfaction

- patients should meet others with same procedure

 

Indication

- young child in whom endoprosthesis has high rate failure

- wide resection about knee

- sciatic nerve preserved

 

Technique

- tibia rotated 180o

- fused to femur

 

Complications

- post operative vascular occlusion

- tibio-femoral pseudoarthrosis

 

Results

- patients can play sports

 

Limb lengthening

 

Usually very large osseous defects

- difficult

- associated with significant complications

- better suited as adjuvant to other procedures or for smaller defects

 

Vascularised fibula graft

 

Advantage over allografts

- more rapid incorporation

- stronger initial construct secondary to graft hypertrophy

 

Disadvantage

- increased surgical time

- surgical site morbidity

- size limitations

- stress fractures

 

Amputation v Limb Salvage

 

Limb Sparing

Amputation

Local Recurrence

5 - 10%

5%

Survival

70%

70%

Functional Outcome

Good

Good

Initial Cost

High

Low

Long term cost

 

 

 

Outcome

- limb salvage often functionally better

- complication rate and incidence multiple surgery higher

 

 

 

Soft Tissue Tumours

Benign

AV Malformations

 

AVM and sclerotherapy0002AVM and sclerotherapy0001

 

Elasto Fibroma Dorsi

Condition

 

Strange scapular tumour

- typically bilateral 

- occurs in lat dorsi

 

Complain of lump which appears around scapula

 

Imaging

 

Looks like muscle on CT

 

Behaviour

 

Benign

 

Histology

 

Shows marked amount of elastin

 

 

 

Fibromatosis

Aggressive Fibromatosis / Desmoid Tumour

 

Benign aggressive 

- most serious of all benign STT

 

Types

 

1.  Intra-abdominal 

- association familial polyposis coli & Gardner's syndrome

- aggressive infiltration

- death from retroperitoneal extension

 

2.  Extra-abdominal 

 

Non-metatasizing locally aggressive STT

- often invasive locally

- similar to low grade fibrosarcoma

 

Classically arise chest wall

- also limbs, head & neck

 

2 types

- superficial fibromatosis - palmar & plantar

- deep fibromatosis

 

Epidemiology

 

F > M 

Average age 40 years

 

Presentation

 

Mass most common

Stiff joint

Neurological compression

Mostly proximal - axilla & groin

 

Pathology

 

Gross

 

Firm mass with white hard cut surface

- may infiltrate local muscle

 

Histology

 

Spindle shaped fibroblasts with plump nuclei & mildly eosinophilic cytoplasm

- often arranged in parallel rows

- separated by variable but large amount of collagen

- may have high degree of cellularity

- very few mitoses & no necrosis

 

Can infiltrate skeletal muscle at periphery

 

Management

 

Wide resection + DXRT

 

80% success

 

Recurrence

 

Intralesional excision 

- 90% recurrence

 

Wide excision 

- 50% recurrence

 

Tumour resection margin

- best prognosticator

- tumour margin clear > 2 mm

 

Radiotherapy alone 

- used for inoperable tumours & after debulking 

 

 

 

Ganglion

Definition

 

Cystic structure lined by a mature capsule of dense fibrous tissue

- contains thick viscous fluid with a high mucopolysaccharide content

- fluid is a myxoid degeneration of synovial fluid

 

Epidemiology

 

Most common in young females

- peak age 15-30

- F:M = 3:1

 

Most common tumour in hand (2/3)

 

Aetiology

 

Unclear

 

Numerous theories

- synovial herniation through capsular defect with development one way valve

- synovial rest

 

Pathology

 

Development

- in early stages, communicate with cavity of tendon or joint

- with time, connection obliterated by fibrous tissue

- become completely enclosed

- fluid becomes inspissated (thickened / dried)

 

Gross

- thin-walled cyst

- may be multiloculated

- easily separated from surrounding soft tissues

- contents clear, viscous & jelly-like

- arthrogram usually demonstrates joint communication

 

Histology 

- wall of paucicellular fibrous connective tissue

- no true epithelial or synovial lining

- contents consist of hyaluronic acid / plasma proteins

 

History

 

Most commonly present with cosmesis issue

 

Appears suddenly or develop slowly

 

Subside with rest & enlarge with activity

 

Location

 

Most common around hands & feet

 

Increased incidence with

- RA

- OA (eg Meniscal cyst)

 

Management 

 

Non-operative

 

Aspiration of cyst

 

Rupture of wall with multiple needle punctures

- instillation of xylocaine & celestone

- 50% recurrence

 

Operative

 

Excision

 

Ankle ganglionFoot Ganglion Excision

 

GA & tourniquet

- excision of lump in full

- attempt to locate and tie off neck

- may excise segment of capsule

 

 

 

Lipoma

Definition

 

Benign adipose tumour

 

Epidemiology

 

Most common mesenchymal neoplasm

- arise from normal fat

- appears during adulthood

 

Clinical

 

80% subcutaneous

- shoulder girdle & proximal thigh most common sites

- well circumscribed mobile, round masse

 

Condition

 

Durcen's Disease 

- multiple lipoma subcutaneous disease

 

MRI

 

Same signal intensity as surrounding fat

 

Lipoma Thigh MRI

 

Classification

 

Divided into 5 subtypes 

 

1.  Simple lipoma

2.  Spindle Cell Lipoma

3.  Pleomorphic Lipoma

4.  Intramuscular & Intermuscular

5.  Angiolipoma

 

1.  Simple Lipoma

 

Incidence

- most common mesenchymal tumour

- tumour of adulthood usually > 40

- multiple in 5%

- 80% of all lipomas

- shoulder & proximal thigh common site

 

Macroscopic

- well circumscribed

- round to ovoid masses

- 4-10cm long

- homogenous pale to bright yellow on cut surface

 

Microscopic

- same as normal fat

- sheets of mature fat cells ovoid to round in shape

- contain single fat droplet 

- peripheral nucleus 

- capillary like vessels are occasionally seen between lobules

- areas of myxoid change or dense fibrous trabeculae are sometimes seen

 

2.  Spindle Cell 

 

Painless firm nodule on neck & shoulder in middle aged men

 

Macroscopic

- encapsulated with a delicate fibrous membrane

- arise within the subcutaneous tissue

- on section may have white to grey myxoid areas

 

Microscopic

- mature fat cells

- variable number of benign spindle cells

- the spindle cells are uniform & arranged in parallel

- mitotic figures are rare

- occasional lipoblasts occur

 

3.  Pleomorphic Lipoma

 

Rare

 

Microscopic

- similar to spindle cell

- has pleomorphic fat cells 

- multinucleated giant cells instead of spindle cells 

 

4,  Intra & Inter Muscular Lipoma

 

Lipoma Intramuscular0001Lipoma Intramuscular0002

 

Macroscopic

 

2 types

- well defined fatty tumour or

- ill defined infiltrative lesion

- unlike superficial lipomas these variants often don't have a capsule

- tend to encircle nerves

 

Lipoma MRI 1Lipoma MRI 2Lipoma MRI 3

 

Lipoma Clinical 1Lipoma Clinical Photo 2

 

Microscopic

- characterized by sheets & nests of mature adipose tissue insinuating between bundles of muscle fibres

- the fat cells are not atypical, & lipoblasts never occur

 

5.  Angiolipoma

 

Angiolipoma MRI0001Angiolipoma MRI0002

 

Atypical Lipoma

 

Microscopic

- have areas of fibrous, myxoid or other connective tissues

- often see secondary changes of calcification & haemorrhage etc

- true lipoma never becomes malignant

 

An atypical lipoma can't be differentiated from well differentiated liposarcoma

- often become large & mimic soft tissue sarcomas

 

Treatment

 

Wide margin

- clinical setting & an adequate tissue sample are required to differentiate liposarcoma

 

 

 

Neurilemmoma

Definition

 

Schwannoma

- benign tumour of nerve sheath

 

Epidemiology

 

Less common than neurofibroma

- occurs in adults

- can occur along any peripheral nerve

- also can occur along a nerve root

 

Usually a large nerve

 

More common in forearm

 

Seen in NF 2 

- acoustic Schwannoma

 

Gross Pathology

 

Usually located eccentrically within nerve 

- compared with NF which are fusiform swellings of the nerve

 

Well encapsulated

- capsule consists of epineurium

- bulges from originating fascicles & pushes aside adjacent fascicles

 

Histology

 

Contain spindled Schwann cells

 

Arranged in alternating hypercellular (Antoni A) & hypocellular (Antoni B) regions

 

Antoni A

- spindle cells form short intersecting fascicles

- whorling pattern with palisading nuclei

- nuclei pallisade & align into columns

- Verocay Bodies - adjacent parallel columns of nuclei separated by fibrillar cell processes

 

Antoni B

- spindle cells twisted & haphazardly arranged

- separated by abundant myxoid ground substance

- may be dilated blood vessels

- more loosely arranged myxoid tissue

 

Immunohistochemistry

 

Positive

- Vimentin

- S 100 strongly +ve

- Leu-7

 

Negative

- Glial fibrillary protein

- Keratin

 

Loss of genes on Chr 22

 

History

 

Painful tender lump

- altered sensation or weak uncommon

- usually along flexor surface

- can increase & decrease in size

 

Examination

 

Soft cystic lump

- mobile transversely but not longitudinally

- strongly positive Tinel's

 

MRI 

 

Show lesion on nerve periphery

 

Compared with NF which is in centre of nerve

 

Management

 

Operative excision

 

Usually removed easily

- open capsule & enucleate with little or no injury to nerve fascicles

- shelling pea from pod

 

If uncertain of diagnosis, obtain fresh frozen section

 

Malignant degeneration occurs, but rare

 

 

 

 

Neurofibroma

Definition

 

Benign tumour of nerve & sheath tissue

 

Epidemiology

 

Most common benign nerve sheath tumour

- associated with NF 1

- usually arises from small cutaneous nerves

 

Classification

 

1.  Localised

- most common type

- usually solitary (90%) with no genetic association

- nil malignant transormation

 

Originate from very small branches of cutaneous nerve

- non encapsulated

- consist of twisted spindle cells arranged in fascicles

- accompanied by wire-like bundles of collagen / myxoid stroma

 

2.  Diffuse

 

Uncommon

- proliferation of spindle cells, collagen & stroma

- permeates subcutaneous tissue & dermis

 

3.  Plexiform

 

Pathognomonic of NF 1

 

Massive expansion of nerve by proliferating tumour cells

- may involve small cutaneous nerve

- ill-defined nodule

- may originate in large nerve

- elephantiasis or gigantism

 

10% malignant transformation

 

Pathology

 

Contain proliferation of

- schwann cells

- perineural cells

- fibroblasts

 

Looks like bland but collagen rich fibrous tumour

- small to moderate amounts of mucoid material

- not encapsulated

 

S-100 stain

- far less intense than in neurilemmoma

 

DDx

 

Schwannomas / neurilemmoma

- contain only Schwann cells

 

Clinical

 

Localised - painless, soft, mobile

 

Diffuse - plaque-like cutaneous mass

 

Plexiform

- ropey redundant mass

- feels like a bag of worms

- 50% of NF patients develop malignancy

 

MRI

 

Diagnosis Neurofibromatosis type 1 (NF1) / Von Recklinghausen 

 

1.  Six or more café-au-lait spots (over 5mm in prepubertal individuals and over 15mm in postpubertal individuals)

2.  Two or more neurofibromas of any type or one plexiform neurofibroma

3.  Freckling in the axillary or inguinal region

4.  Optic glioma

5.  Two or more Lisch nodules (iris hamartomas)

6.  A distinctive osseous lesion such as sphenoid dysplasia or thinning of the long bone cortex with or without pseudarthrosis

7.  A first degree relative (parent, sibling, or offspring) with NF1 by the above criteria

 

Management

 

Localised

 

Surgical Indications

- pain

- nerve dysfunction

- rapid growth 

- suspicion of malignancy

 

Technique

- not easily separated from nerve

- excision usually involves partial resection of nerve

- if nerve small is sacrificed

- if nerve large and important need interposition graft

 

Plexiform 

 

Surgical Indications

- persistent symptoms / pain & numbness

- features of malignancy

 

Features of malignancy

- enlarging

- new or increasing pain

- perform biopsy

 

Technique

- excision difficult

- entering nerves usually sacrificed

- graft if needed

 

 

 

Malignant

Liposarcoma

Definition

 

STS composed of malignant lipoblasts

 

Epidemiology

 

Common 

- 10% of STS

- second only to MFH

 

Occurs almost exclusively in adults

 

Males age 40-60

 

Can be multiple origin -> examine patient

 

Rarely arise from lipoma

 

Differentiation

 

Many MFH's classified as liposarcoma in past

 

Liposarcoma S-100 +ve 

 

MFH negative to immunohistochemistry

 

Sites

 

Thigh / retroperitoneum / popliteal fossa / inguinal region

 

Almost always subfascial

- often between muscles or perivascular

 

Clinical

 

Painless mass or mild dull ache

 

No systemic complaints

 

Usually present late when tumour large

- especially retroperitoneal 

- no pain as tumour deep

 

Xray

 

Liposarcoma Xray

 

MRI

 

Deep to fascia / heterogenous

 

Liposarcoma Buttock MRILiposarcoma MRI 2

 

Liposarcoma

 

Metastasis

 

Pattern different to other STS

- 1/2 metastasise to lung

- 1/2 unusual non lung sites - retroperitoneum / mediastinum

 

Prognosis

 

Depends greatly on subtype & grade

 

Pathology

 

Gross

 

May quite large especially in retroperitoneal region

- well circumscribed & multilobulated

- soft, firm or rubbery

- colour based on mix of fat / myxoid / fibrous

- high grade = Necrosis

 

Histology

 

Diagnose by identifying typical lipoblasts 

- signet ring cells

- contains 1 or 2+ round cytoplasmic fat droplets which form sharp, scalloped indentatons on the nucleus

 

Liposarcoma vs Atypical Lipoma

 

Often difficult to differentiate low grade well differentiated liposarcoma from atypical lipoma

- if subfascial & non homogenous on MRI

- treat as STS 

- even if biopsy suggests benign

- high sampling error with biopsy

 

Classification

 

5 Types Histology

- treatment depends on grade & histology

 

1.  Well-Differentiated 30% 

- low grade 70% 5 year survival

- lipoma like

- risk of distant metastasis very low

- often recur after local excision

- death only with retroperitoneal metastasis

 

2.  Myxoid 50%

- low-grade 70% 5-year survival

- delicate plexiform capillary network

- translocation between 12 and 16

 

3 . Round Cell 10%

- high-grade 40% 5-year survival

- sheets poorly differentiated rounds cells

 

4.  Pleomorphic 20%

- high-grade 40% 5-year survival

- multivacuolated lipoblasts

 

5.  Dedifferentiated 

- due to heterogenity may be confused with other lesions

- myxoma / pleiomorphic lipoma/ myxoid chondrosarc / melanoma

- metastatic adenocarcinoma especially RCC

 

Management

 

Wide excision with radiotherapy

 

Results

 

Longhi et al J Clin Oncol 2008

- retrospective review

- compared preRT / postRT / chemo and no adjuvant treatment

- postop RT had best 5 year disease free survival at 82%

 

 

MFH

Definition

 

Malignant Fibrous Histiocytoma

 

Characterised by heterogenous population of pleomorphic spindle cells

- organised in a characteristic storiform or "starry night" pattern

 

Cell of origin unknown 

- primitive mesenchymal cell

- allowing both features of a macrophage (hence histiocyte)

- and collagen producing cell (hence fibroblast)

 

Epidemiology

 

Most common STS

- > 50 years old

- diagnosis largely replaced fibrosarcoma

 

Becoming less common again

- many being reclassified 

- basis of immunohistology 

- turning out to be poorly differentiated liposarcoma or malignant muscle tumours

 

NHx

 

Aggressive

- majority Grade II

 

Rare cases of multicentric tumours reported

 

Classification

 

Soft Tissue

 

Arise from primitive mesenchymal cells

 

Bone

 

A.  Primary 80%

- arise from bone mesenchymal cells

- exhibits both histiocytic & fibrous properties

 

B.  Secondary 20%

 

Occur in abnormal bone

- Paget's disease

- bone infarct 10%

- post DXRT

- multiple osteochondromatosis

 

Location

 

Most common in thigh

- 85% deep to fascia

- thigh > leg > arm > forearm

 

Retroperitoneal > 15cm

 

Bone 

- knee / femur / tibia / humerus

 

Clinical

 

"An aggressively enlarging, deep, and surprisingly mildly symptomatic soft tissue mass characterizes soft tissue MFH"

 

X-ray

 

Normal except for ST shadow

 

CT / MRI 

 

Large soft tissue mass

- arising from muscle

- patchy non-homogeneous areas

 

MFH Thigh Coronal MRIMFH Thigh MRI Axial

 

Bone

- metaphyseal purely lytic lesion

- ill-defined margins with cortical destruction

- no intra-tumour calcification

- may be seen arising from area of bone infarction 

 

Pathology

 

Gross

 

Solitary or multinodular

- margin usually discrete

- has fish-flesh appearance

- colour varies with proportion of stromal to cellular elements

- myxoid variant has white-grey, soft mucoid tumour lobules

- 5% undergo extensive necrosis & haemorrhage

 

Histology

 

Basic cellular constituents

1.  Fibroblasts in Storiform pattern

2.  Histiocyte like cells with vacuolated cytoplasm and evidence of phagocytosed hemosiderin, lipofuscin etc

3.  Mesenchymal cells

4.  Giant cells

5.  Inflammatory cell infiltrate not uncommon

 

Management

 

Principle 

 

Local control / wide resection if able

 

Radiotherapy if doubt about margins

 

Chemotherapy for metastasis

 

Prognosis

 

Best in I A/B 

- 50% 5 year survival

- 85% if < 5 cm

 

50% metastasis on diagnosis

 

50% recurrence rate

- local recurrence is aggressive

- causes significant morbidity

- doesn't alter overall survival

 

 

Other

Leimyosarcoma

Fibrosarcoma

Clear cell sarcoma

Epitheliod sarcoma

Neurosarcoma

 

Leimyosarcoma

 

Definition

 

Tumour of smooth muscle

- ? arises from vein wall

- very rare

- can arise from Leiomyoma

 

Clinical

 

Most common in elderly

 

Usually found in deep soft tissues

- especially retroperitoneum

- extremities

- GUT

- can see in uterine fibroids

 

Associated with NV bundle

 

Most common peripherally in

- groin

- popliteal fossa

 

Leimyosarcoma Femoral Vein MRI Coronal T2Leimyosarcoma Femoral Vein MRI Axial T2

 

Behaviour

 

Aggressive - early metastasis

 

Treatment

 

As for STS

- wide resection & DXRT

 

Fibrosarcoma

 

Definition

 

Malignant spindle cell neoplasm 

- produces a sparse to moderate amount of collagenous matrix 

- has no other matrix differentiation

 

Epidemiology

 

Since MFH, true Fibrosarcoma <10% STS

 

Primary tumour of mid-adults

- typically adult 20-60 yrs

 

M = F

 

Usually lower limb

 

Infantile & Congenital types exist

- better prognosis

- distal

 

DDx

 

FS v Fibromatosis

- the site, age, & histological findings must be carefully evaluated

- difficult to distinguish low grade fibrosarcoma from fibromatosis.

 

Fibrosarcoma

 

Pathology

 

Gross 

 

Arise from deep fascial or aponeurotic elements

- small tumour - well circumscribed

- larger - infiltrative

 

Histology

 

Principle cell the fibroblast

- spindle cell capable of producing collagen

- collagen easily identified in well differentiated specimens

 

Two varieties

 

1.  Well differentiated

- uniform spindle cells in fascicles

- herring bone pattern

 

2.  Poorly differentiated

- poor fascicular pattern

- increased pleomorphism

- many mitoses

- difficult to pick from MFH & both behave the same anyway

 

Immunohistochemistry

 

Masson's trichrome stain confirms the presence of collagen

 

Clear Cell Sarcoma

 

AKA Malignant Melanoma of the soft tissue

 

Characteristics

 

Small tumour 

 

Arises in conjuction with tendons & aponeuroses

- common around foot & ankle 50%

- young patients 20 - 40 years

 

Characteristic translocation

- t(12:22)

 

Clinical

 

Young male with tumour in foot and ankle

- think of clear cell sarcoma or synovial sarcoma

 

Metastasis

- lymphatic & haematogenous spread occurs

- enlarged local nodes require dissection

 

Pathology 

 

Gross

- solitary or multinodular firm mass 

- attached to tendons /aponeuroses

- rarely > 6cm 

- white to brown on its cut surface

 

Histology

 

Distinct fascicles & nests of spindle cells 

 

Uniform plump spindle cells 

- pale cytoplasm

- contain glycogen 

- melanin is present in 50%

 

Immunohistochemistry

 

Fontana preparation for Melanin

PAS for Intracellular Glycogen

 

Epithelioid Sarcoma

 

Characteristics

 

Odd small STT

- often misdiagnosed as benign ganglion

- ganglions occur in typical places

- if not, suspect more sinister diagnosis

 

50% arise forearm / wrist 

- number 1 Sarcoma of hand

 

Can arise in the dermis 

- can present with nodule or ulceration 

- simulates a cutaneous lesion eg granulomatous dermatitis

 

Tends to lymph node spread

 

Young adults compared with other STS

 

Pathology

 

Gross 

- arises in deep tissues especially near tendons, fascia 

- often firm & multinodular

- occasionally central necrosis 

 

Histology

 

Nodules or granuloma like collections of epithelioid cells

 

Epithelioid cells

- large cells

- deeply eosinophilic cytoplasm

- may transform to spindle cells

 

Characteristic feature is that of diffuse infiltration of tendon & fascial structures by elongated nests of tumour cells

 

Neurofibrosarcoma

 

Neurofibrosarcoma MRINeurofibrosarcoma Axial MRI Neurofibromatosis

 

AKA Malignant Schwannoma

 

Arise from peripheral nerves

 

Epidemiology

 

10% of STS

 

50% have NF

 

NF 

- 10% life risk & increases with age 

 

If not associated with NF then occur in older patients

 

Clinical

 

Painful mass

- previously painless, small stable tumour

- now painful

- enlarging

 

Often presents with neurological symptoms (arise on nerve)

- pain / paraesthesia / weakness

 

Pressure

- elicit pain & parasthesia in distribution of nerve

 

Site 

- Brachial plexus

- lumbosacral plexus

- major nerve trunks - especially the sciatic nerve

 

MRI

 

The MRI does not reliably distinguish a benign neurofibroma from one that has undergone transformation to a neurosarcoma

 

Pathology

 

Gross

 

Fusiform or bulbous swelling of a peripheral nerve

- usually deep

- infiltrates as it enlarges

- grey to white in cross section 

- areas of necrosis

 

Histology

 

Basic pattern of intersecting spindle cell fascicles

- herringbone

- very similar to fibrosarcoma & leiomyosarcoma

- wavy nuclei

- pallisading pattern ± whorled

- rare epithelioid variant

- similar melanoma or carcinoma

 

Prognosis

 

Most are high grade malignancies

- five year survival rate < 50%

- regional metastases to LN uncommon

 

Lung and bone are the commonest sites of distant metastases. 

 

Because of their association with the major neurovascular bundles, the vast majority of the lesions present in Stage II-B

Solitary neurosarcomas have a better prognosis than those associated with neurofibromatosis 1

Principles of ST Sacromas

Most common sarcomas Sarcoma Arm

 

1. MFH

2. Liposarcoma

3. Rhabdomyosarcoma (Paediatric)

4. Synovial Sarcoma 

5. Leiomyosarcoma

6. Fibrosarcoma

 

Ten Tissues of Origin

 

1.  Adipose / LS

2   Fibrous / FS

3.  Fibrohistiocytic / MFH

4.  Muscle / Leiomyosarcoma /  Rhabdosarcoma

5.  Vascular Tissue 

- haemangioendothelioma / angiosarcoma / kaposi's sarcoma

- malignant glomus / malignant haemangiopericytoma

6.  Synovial / Synovial Sarcoma

7.  Nerve / Malignant Schwannoma 

- neurofibrosarcoma

8.  Autonomic Ganglia / Neuroblastoma

9.  Bone / Cartilage - Extraskeletal OS & CS

10.  Uncertain

- alveolar soft part sarcoma / epitheliod sarcoma / extra-skeletal ewing's

- clear cell sarcoma / malignant melanoma of soft parts

 

2 most important prognostic factors

 

Size

Grade including metastases

 

DDx soft tissue mass

 

Malignant ST lesion

 

Benign ST lesion

- vascular (hemangioma, AVM, lymphangioma, glomus)

- neurogenic (NF, schwannoma)

- muscular (leiomyoma)

- fibroblastic (desmoid tumour, fibromatosis)

- fat (lipoma)

- simple cyst

 

PVNS / synovial chondromatosis

 

MO

 

FB

 

Malignancy - melanoma, metastatic

 

Clinical

 

Present as painless ST mass

- increasing in size

- becoming painful

 

Very rare to have systemic signs

 

Occurs 30 - 60 years

 

X-ray

 

DDx calcification

- hemangioma

- MO / HO

- synovial sarcoma / liposarcoma

 

MRI

 

Aim

- detects ST tumours

- determines anatomical extent 

- determines depth

- compartments / NV bundles

- characterises tumour

- plans resection / biopsy / approach

 

Staging

 

Locally

- MRI for soft tissue component

- MRA for vessel involvement

- +/- CT if intra-osseous

 

Systemic

- bone scan to detect intraosseous spread

- CXR and CT chest as per usual

 

Site

 

40% in lower limbs

50% in limbs

Remainder head neck and trunk

 

NHx

 

Act similar to sarcomas of bone

 

Exceptions

- usually remain intracompartmental

- significant incidence of lymphatic involvement in synovial and alveolar soft part sarcoma

 

Benign v Malignant

 

  Malignant Benign
Size > 5 cm < 5 cm
Location Deep to fascia Superficial to fascia
Feel Soft, mobile, nontender Firm, fixed, tender

 

Grade 

 

Depends on the usual histological findings

- mitoses, pleomorphism, necrosis, nuclear atypia

- can be difficult

 

Exception

- synovial sarcoma

- usually high grade

 

Staging

 

American Joint Committee on Staging of STS 1993

 

  Grade Size Spread
IA Low < 5cm  
IB Low > 5cm  
IIA Intermediate < 5cm  
IIB Intermediate > 5 cm  
IIIA High < 5 cm  
IIIB High > 5cm  
IVA Any   Lymph node
IVB Any   Metastasis

Modification 1997

 

Only low and high grades

Size

Depth

- important to prognosis

- i.e. subfascial

 

Prognosis

 

Now 5 year survival 50 - 80%

- combination wide resection and DXRT

 

Local recurrence doubles metastasis risk

 

Death from

- primary diseases / local recurrence

- lung / bone metastasis

 

Unfavourable 

- > 5 cm

- deep / extracompartmental

- inadequate excision

- histological high grade

 

Management

 

Principles

 

Wide Resection + DXRT 

- wide resection for local control

- DXRT to prevent local recurrence

- role of chemotherapy in adult STS uncertain

 

DXRT

 

Addition of DXRT has allowed limb salvage surgery without recurrence 

 

Irradiate all tissue at risk

- use filters & radiosensitisers

- local morbidity has decreased significantly in recent times

 

Pre-op DXRT

- 50 Gy in 2 Gy fractions

- higher doses than carcinoma

- shrinks tumour & makes resection easier

- increased complication rates

- surgery after 2-4 wks to allow skin to settle

 

Sarcoma Neck Pre and Post Radiation0002Sarcoma Neck Pre and Post Radiation0001

 

Post-op Brachytherapy ~ 10 Gy

 

Chemotherapy

 

No conclusive studies demonstrating efficacy of chemotherapy

 

Exception

- paediatric rhabdomyosarcoma

- high grade sarcomas

- treatment for lung mets (50% response rate)

 

Surveillance

 

For 10 years

- CXR every 3/12 for 2 years then 6/12 for 5 years

- physical examination of site for recurrence

- MRI site if concern

 

Recurrence

 

Local recurrence

- surgical excision & adjuvant DXRT

 

Lung Metastasis

- chemotherapy +/- surgical excision

- 20% survival at 5 years

 

Paediatric ST Sarcoma 

 

Different entity

- histololgically small cell

- different response to treatment

- good response to chemotherapy

- respond to surgical measures better as are fibrous based

 

Tumours

- rhabdomyosarcoma

- soft-tissue Ewing's

- PNET

- neuroblastoma

 

Rhabdomyosarcoma

Definition

 

Malignant tumour of striated muscle

 

Juvenile variety arises from mesenchyme

 

Thigh sarcomaSarcoma Thigh Axial

 

Epidemiology

 

Most common malignant ST Tumour in children (< 15 years)

- groin, head & neck

 

Recently, most adult rhabdomyosarcs reclassified as MFH

 

Types 

 

Four types "BEPA"

 

1.  Embryonal

 

Most common type 2/3

- arises in groin & head & neck > Urinary Tract & Retroperitoneum

- not common in extremities

- occurs in age < 10 years

- very aggressive

 

Histology

- poorly differentiated rhabdomyoblasts

- limited collagen matrix

- small blue round cell

 

DDx

- undifferentiated carcinoma / small cell OS / neuroblastoma / lymphoma / PNET / Ewing's

- IH desmin / myoglobin

- EM cross striations

 

2.  Alveolar

 

More common in extremities than trunk

- older 

- occurs in age 10-25 years

- ggressive

- histology similar to embryonal

- well differentiated round cells arranged in alveolar pattern separated by thick fibrous septa

 

3.  Botryoid 

 

"Bunch of Grapes"

- uncommon

- ccurs in hollow viscus

- particularly the bladder

- grape like clusters of round cells beneath the mucosal lining of hollow organs

- EM studies: sarcomere formation and cross striations

 

4.  Pleomorphic

 

Rare

- occurs in adults

- deep portions of the extremities

- arises skeletal muscle

- dark red lobulated mass

 

Histology

- spindle shaped cells with marked variation in size / shape

- bizarre gigantic cells 

- cells can resemble a wrist watch

 

DDx

- MFH

- EM / IHC

 

Genetics

 

Characteristic translocation

- t(2:13)

 

Management

 

Principles

 

Neoadjuvant Chemotherapy

- exception to usual management for STS

 

Wide surgical resection 

- total excision of involved muscle

 

DXRT

- if resection not possible or incomplete

 

Prognosis

 

Depends on resection & stage

- complete resection, 85% 5 year survival

- macroscopic residual disease or distant metastases, 50% 5 year survival

 

 

Synovial Sarcoma

Epidemiology

 

4th most common STS

- 10-35% of STS

 

Peak age 3rd-4th decade

- rare in children

 

Pathology

 

Cellular characteristics suggest tumour arises from primitive synovial cells

- rarely actually occurs within joint

 

Characteristic

 

Occasionally metastasis to lymph nodes (5-7%) 

- like Epitheloid Sarcoma 

- feel nodes in examinaiton

 

Classically show mineralization

- see on knee X-ray

 

Most common STS of foot

 

Synovial Sarcoma Foot MRI0001Synovial Sarcoma Foot MRI0002

 

Rarely intra-articular

 

Location

 

Deep soft tissues

- often centered on tendons, bursa and joints

- head, neck & trunk 15%

- extremities 50% / knee

- hands & feet 10% / often mistaken for ganglion

 

X-ray

 

May have calcification or ossification in tumour

 

DDx Soft Tissue Lump with calcification

 

Malignant ST tumour

 

Benign ST tumour - hemangioma / AVM

 

Malignant bone tumour - OS

 

Myositis Ossification

 

DDx lymph node metastasis

 

Clear cell sarcoma

Rhabdomyosarcoma

TB! - Calcified lymph node

 

MRI

 

Knee

- heterogenous mass, not communicating with joint

 

DDx Baker's cyst

- semimembranosus

- communicates with joint

- between semimebranosus tendon and medial head gastrocnemius

 

Bakers Cyst MRIBakers Cyst MRI

 

Histology

 

Difficult to grade 

- all considered high grade

- more extensive calcification suggests better prognosis

 

A. Biphasic Type

- classic pattern

- contains 2 distinct cell types

- epitheliod cells which resemble adenocarcinoma

- form gland like structures lined by cuboidal cells

- malignant spindle cells

 

B. Monophasic Type

- as common as classic biphasic

- spindle cells only 

- difficult to DDx from fibrosarcoma

 

Cytogenetics

 

Have a characteristic translocation

- t(X:18)

 

Management

 

Pre-op DXRT & Resection

 

Limb salvage may be possible

- amputation preferred in hand & foot

 

Post operative chemotherapy

 

Prognosis

 

70% 5 year survival rate

 

Metastases occur in 50%

 

Poor prognosis 

- local recurrence 

- inadequate resection 

- large size / monophasic / mets

 

Better prognosis

- heavily calcified

- <5cm

Synovial Proliferations

Lipoma Arborescens

 

Lipoma Arborescens Knee ArthroscopyLipoma Arborescens Knee Arthroscopy 1Lipoma Arborescens Knee Arthroscopy 2

 

Definition

 

Proliferative synovial condition

- characterised by synovial villi

- centre is lipoma

 

Clinical

 

Lipoma Arborescens

 

Most common in the knee

- massive synovial swelling

- large effusion

 

Problems

 

Can lead to early degenerative change

 

Aetiology

 

Unknown

- postulated to be related to minor knee trauma

 

Diagnosis

 

MRI

- synovial proliferation

- signal similar to surrounding fat

 

Lipoma Arborescens MRI AxialLipoma Arborescens MRI SagittalLipoma Arborescens OCD

 

Arthroscopy

- yellow brown polypoid / frond like villous synovitis

 

DDX

 

PVNS

Synovial Chondromatosis

 

Management

 

Options

 

1.  Arthroscopic Debridement

 

2.  Open Debridement

 

3.  Radionuclide Injection

- Yttrium 90

- not proven to work

- risk skin necrosis

 

PVNS

Definition

 

Pigmented Villo-Nodular Synovitis

- benign inflammatory process that arises in synovial tissues

- contains significant amounts of hemosiderin

 

Epidemiology

 

Age: 20 - 50

Sex: M > F

 

Types

 

A.  Diffuse

- throughout joint synovium

- more difficult to treat / excise fully

 

 PVNS Knee ArthroscopyPVNS Localised

 

B.  Localised

- just one area of synovium

- i.e. suprapatella / medial or lateral gutter

 

PVNS Knee MRI LocalisedPVNS LocalisedPVNS Knee LocalisedPVNS Localised

 

Site

 

Major joints

- knee, hip, shoulder, and ankle

- has been observed in all joints

 

Usually mono-articular

- occasionally multiple joints

 

In aggressive cases, PVS may involve adjacent bone

 

Pathogenesis

 

The cause is unknown

 

Theories

 

1.  Recurrent hemarthrosis 

- cavity of the involved joint is recurringly filled with old unclotted blood

- hemosiderin is a prominent gross and histological finding

- may lead to

 

2.  Inflammatory process 

- marked synovitis

- no virus, bacteria or other inflammatory stimulant has been demonstrated

 

3.  ? Neoplasm

- there are scattered reports of distant metastases to the lungs and other organs leading to death

 

Natural History

 

The process is intermittently progressive

- over a period of several months or years

- diffuse synovial involvement

 

Progressive destruction of the articular cartilage and subchondral bone

- results in severe degenerative arthritis

 

Extensive soft-tissue extension occurs

- may produce peripheral neuropathy by neurovascular bundle involvement

 

In aggressive cases, PVNS may involve adjacent bone

- pathologic fracture secondary to subchondral bone invasion is occasionally seen

- especially in the femoral neck

 

Clinical

 

Intermittent joint effusion 

Modest discomfort

Antecedent trauma 

- often recounted but difficult to relate to the development of PVNS

 

Aspirate

 

Blood tinged / xanthochromic

- in absence of trauma

- highly suspicious of PVNS

 

X-ray

 

Soft tissue swelling 

 

Arthritic changes

 

Bone destruction

- invasion of adjacent metaphyseal cancellous bone

- may be suggestive of neoplasm

 

Bone Scan

 

Increased uptake +++

 

MRI

 

Characteristic T2

- heterogenous picture

- high intensity signal from vascular component

- low intensity signal from hemosiderin 

 

Hemosiderin has low signal intensity on TI and T2

 

PVNS Knee MRIPVNS MRI T1

 

Assess involvement of knee areas

- suprapatella

- medial and lateral gutters

- posterior compartments

- femoral notch

 

Nodular

 

PVNS 1PVNS 2PVNS 3PVNS 4PVNS 5

 

Diffuse

 

PVNS Diffuse 1PVNS Diffuse 2PVNS DiffusePVNS Diffuse 4PVNS Diffuse

 

DDx

 

Haemophilia

Lipoma arborescens

Synovial chondromatosis

 

Management

 

Synovectomy

 

Complete synovectomy

- dissecting the synovium and intermediate layers

- preserve deep fibrous layers and ligaments

- need to remove all affected synovium for best results

- meticulous surgical technique required

 

Options

 

Open

- posterior recess difficult to access

- or if extracapsular

 

PVNS Posterior KneePVNS Posterior Knee

 

Arthroscopic

- often need posterior cannulas / portals

- takes up to 2 hours

 

PVNS ACL ArthroscopyACL post PVNS Debridement

 

PVNS debridement kneePVNS Knee

 

Results

 

Kim et al Clin Orthop Research 2000

- 11 patients with localised PVNS of the knee treated arthroscopically

- no recurrences at 2 - 4 years

 

Chin et al JBJS Am 2002

- treatment of recurrent PVNS in 40 patients

- repeat surgery with post op radiation synovectomy or DXRT if residual disease

- best outcomes with complete surgical excision of all disease

 

Synovial Chondromatosis

DefinitionSynovial Chondromatosis Knee MRI

 

Chondroid Metaplasia of synovium affecting large joints

 

Nodules of hyaline cartilage

- formed in the subsynovial layer of joint capsules

 

Epidemiology

 

Rare lesion

Most common in 20's and 30's

Sex: M > F (2:1)

Monoarticular

 

Site

 

Any synovial lined joint, tendon or bursal cavity 

 

Marked predilection for large joints 

 

Knee (70%) > Hip > Elbow > Shoulder

 

Subtypes

 

Primary

 

Secondary

- more common

- preexisting OA/RA/AVN/Charcot/TB

 

Pathology

 

Primary

 

Mesenchymal cells in joint capsule (subsynovial layer) become Chondroblasts instead of Fibroblasts

- form nests of cartilage

- nests grow & protrude into joint

- covered by synovium

- eventually become pedunculated into joint

- connected by synovial stalk

 

Then break off & lie free in joint as cartilaginous LB

- Continue to grow in joint 2° synovial diffusion

- can undergo secondary calcification and ossify

 

Secondary

 

Patient with shearing chondral injury

- cartilage cells can seed synovium and continue to grow

 

Patella Chondral DamageSecondary ChondromatosisSecondary Synovial Chondromatosis

 

Histology

 

Central necrotic area that may be calcified

- peripheral ring of viable chondrocytes 

- disorganized chondrocytes with cellular atypia

- can be difficult to pick from chondrosarcoma

 

Stages

Milgram 1977 JBJS

 

Phase 1 - Early; Synovitis, no loose bodies

Phase 2 - Transitional ; Synovitis & loose bodies

Phase 3-  Late ; Loose bodies, no synovitis

 

Clinical

 

Pain & swelling

Loss of ROM

Locking & giving way

Multiple loose bodies

 

X-ray

 

Calcified lesions

 

Loose bodies in suprapatellar pouch

 

MRI

 

Synovial Proliferation

 

Subsynovial masses

- same signal intensity as cartilage

 

Synovial Chondromatosis MRI KneeMRI Knee Synovial Chondromatosis

 

Arthroscopy

 

Synovial proliferation

- localised or generalised

- can see cartilage growing from synovium

 

Multiple loose bodies +++

 

Knee ChondromatosisKnee Chondromatosis

 

Knee ChondromatosisKnee Chondromatosis

 

Management

 

Timing

 

Early surgery to prevent secondary degeneration

 

Biopsy

 

Hip

 

Options

 

1. Arthroscopic

 

2.  Open without dislocation

- leave synovium on ligamentum teres

 

3.  Open with dislocation

- lower recurrence

- risk AVN

- Ganz anterior open dislocation

 

 

Results

 

Boyer et al JBJS Br 2008

http://boneandjoint.org.uk/content/jbjsbr/90-B/3/314.full.pdf

- arthroscopic debridement in 111 patients, follow up average 6 years

- 20% required subsequent repeat arthroscopy

- 38% required subsequent open synovectomy

- 20% went on to require THR

 

De Sa et al Arthroscopy 2014

- systematic review of arthroscopic hip debridement

- 7.1% recurrence rate

- minor complication rate 1%

 

 

Lim et al JBJS Am 2006

 

- 21 cases treated with open synovectomy

- 8 treated with arthrotomy alone with 2 recurrences

- 13 treated with surgical dislocation with no recurrences

- recommend dislocation with extensive disease

 

Knee

 

Results

 

Ogilvie-Harris et al Arthroscopy 1994

- 13 patients with generalised disease

- 5 treated with removal loose bodies only

- 8 with synovectomy

- lower recurrence in synovectomy group

 

Shoulder

 

Results

 

Lunn et al JBJS Br 2007

- 15 patients, half primary and half secondary

- arthritic changes present in 8 prior to treatment, 11 after

- arthroscopic synovecotmy + open biceps tenotomy if this area involved

- good pain relief but no improvement in ROM