BONE TUMOURS Flashcards
What is an osetoma?
benign ‘overgrowth’ of bone, most typically occuring on the skull
What is an osetoma associated with?
Gardner’s syndrome (a variant of familial adenomatous polyposis, FAP)
What is an osteochondroma/exotosis?
MOST COMMON benign bone tumour
epidemiology of osteochondroma
males
patients <20 yrs
features of osetochondroma/extosis
cartilage-capped bony projection on the external surface of a bone
what is a giant cell tumour
tumour of multinucleated giant cells within a fibrous stroma
benign
epidemiology of giant cell tumour
20-40 years
where does the giant cell tumour occur?
epiphyses of long bones
what does X-ray show in giant cel tumour
double bubble
soap bubble
what are examples of benign bone tumours
- osetoma
- osteochondroma
- giant cel tumour
What is an osteosarcoma?
most common primary malignant bone tumour
types of malignant tumours
osteosarcoma
ewings sarcoma
chrondrosarcoma
who is an osteosarcoma most commonly seen in?
children and adolescents
where does an osteosarcoma tend to occur in the body?
metaphyseal region of long bones prior to epiphyseal closure, with 40% occuring in the femur, 20% in the tibia, and 10% in the humerus
what does xray show in osteosarcoma
codman triangle - from periosetal elevation and sunburst pattern
what mutation increases risk of osteosarcoma and what condition is it associated with
mutation of Rb gene - retinoblastoma
what are the other predisposing factors of osteosarcoma
Paget’s disease
radiotherapy
what is Ewings sarcoma
small round blue cell tumour
who is Ewings sarcoma seen in
children and adolescents
where does Ewings sarcoma occur
pelvis and long bones. Tends to cause severe pain
what thrombosis translocation is it associated with and what gene product
t(11;22) translocation which results in an EWS-FLI1
what does the xray show
onion skin appearance
what is chondrosarcoma?
malignant tumour of the cartilage
where does chondrosarcoma tend to affect?
axial skeleton
who does chondrosarcoma tend to affect
middle aged
