Bone tumours

Question 1

Benign ‘overgrowth’ of bone, most typically occuring on the skull

Associated with Gardner’s syndrome (a variant of familial adenomatous polyposis, FAP)

Answer 1

Osteoma

Question 2

Most common benign bone tumour

More common in males, usually diagnosed aged < 20 years

Cartilage-capped bony projection on the external surface of a bone

Answer 2

Osteochondroma

Question 3

Tumour of multinucleated giant cells within a fibrous stroma
Peak incidence: 20-40 years
Occurs most frequently in the epiphyses of long bones
X-ray shows a ‘double bubble’ or ‘soap bubble’ appearance

Answer 3

Giant cell tumour

Question 4

Give examples of benign bone tumours

Answer 4

Osteoma
osteochondroma
giant cell tumour

Question 5

Most common malignant bone tumour
Usually in children and adolescents
Occurs in metaphyseal region of long bones prior to epiphyseal closure (femur/tibia/humerus)
XR shows Codman triangle (from periosteal elevation) and ‘sunburst’ pattern
Risk factors: Mutation of Rb gene, Paget’s disease, RTX

Answer 5

Osteosarcoma

Question 6

small round blue cell tumour
seen mainly in children and adolescents
occurs most frequently in the pelvis and long bones
Severe pain
t(11;22) translocation = EWS-FLI1 gene product
XR shows ‘onion skin’ appearance

Answer 6

Ewing’s Sarcoma

Question 7

malignant tumour of cartilage
most commonly affects the axial skeleton
more common in middle-age

Answer 7

Chondrosarcoma