Approach to Primary Bone Tumour



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



- 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?


Cortical expansion

Cortical erosion / breakthrough



Wide / narrow zone of transition / permeative margins

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

- wide / infiltrative / bad sign


3.  What is the bone doing to it?


Periosteal reaction

- Codman Triangle / Sunburst / Onion Skinning


Reactive rim

- Sclerotic = slow growing

- Ill defined = fast growing


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




Fibrous dysplasia

Osteoid Osteoma / Osteoblastoma / Osteosarcoma

Giant cell tumour

Metastasis / myeloma


Enchondroma / Chondroblastoma / Chondrosarcoma

Hemangioma / HPTH

Infection / Intraosseous ganglion or lipoma / Infarct

Non Ossifying Fibroma / Neurofibroma


Simple bone cyst / Synovial Proliferation




Malignant pain - night time, severe, increasing


Red flags - fever, night sweats, weight loss, anorexia


Widhe et al, JBJS 2000

- 85% of osteosarcomas present with pain related to a "strain"

- only 21% of osteosarcoma present with night pain




Soft tissue mass = aggressive lesion


Pathology tests


Serum electrophoresis / urine Bence Jones (Multiple myeloma)

PSA - prostatic cancer (PSA < 10 suggests < 1% chance of metastatic prostate cancer)

ESR / CRP - non specific (increased in infection / Ewing's / multiple myeloma / 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



- accurately define the extent of the disease

- prior to proceeding with biopsy and definitive treatment


Local / Cross sectional imaging




Best for assessing mineralisation & bony details

- benign bone tumours

- violation of cortex

- matrix mineralisation

- shows areas that plain xray visualises poorly i.e. spine / pelvis




Best for assessing soft tissue component



- cortical breakthrough

- soft tissue extension

- marrow involvement / intramedullary spread

- relationship to NV bundle

- joint & epiphyseal involvement




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



- identify primary lung cancer that may have metastasised to bone

- identify liver and lung metastasis


Lung Metastasis CT Chest


3. Biopsy




A.  To determine whether benign or malignant

B.  To determine specific cell type

C.  To determine grade


See Principles of Biopsy


4. Definitive Treatment


Sarcoma requires referral to specialist service