Bone Tumours Flashcards
name the benign bone tumours
- osteoma
- osteochondroma (exotosis)
- giant cell tumour
where does osteoma typically occur?
skull
what is osteoma?
benign ‘overgrowth’ of bone
what is osteoma associated with?
gardner’s syndrome
(a variant of familial adenomatous polyposis)
what is the most common benign bone tumour?
osteochondroma
who is typically diagnosed with osteochondroma?
male <20 years old
what is osteochondroma?
cartilage-capped bony projection on the external surface of a bone
what is giant cell tumour?
tumour of multinucleated giant cells within a fibrous stroma
what is the peak incidence of giant cell tumour?
20-40 years
where does giant cell tumour most commonly occur?
epiphyses of lone bones
what appears on x-ray in giant cell tumour?
‘double bubble’ or ‘soap bubble’
name the malignant bone tumours
- osteosarcoma
- ewing’s sarcoma
- chondrosarcoma
what is the most common primary malignant bone tumour?
osteosarcoma
what age are you most likely to develop osteosarcoma?
children and adolescents
where does osteosarcoma typically present?
metaphyseal region of lone bones prior to epiphyseal closure
* femur (40%)
* tibia (20%)
* humerus (10%)
what does x-ray show in osteosarcoma?
- codman triangle (from periosteal elevation)
- ‘sunburst’ pattern
what are the risk factors for osteosarcoma?
- mutation in Rb gene (association with retinoblastoma)
- paget’s disease
- radiotherapy
what is ewing’s sarcoma?
small round blue cell tumour
what age are you most likely to develop ewing’s sarcoma?
children and adolescents
where does ewing’s sarcoma most commonly develop?
pelvis and long bones
how does ewing’s sarcoma present?
severe pain
what does x-ray show in ewing’s sarcoma?
‘onion skin’ appearance
what genetic abnormality is ewing’s sarcoma associated with?
translaction (11;22)
results in an EWS-FLI1 gene product
what is chondrosarcoma?
malignant tumour of cartilage
where does chondrosarcoma most commonly develop?
axial skeleton
what age are you most likely to develop chondrosarcoma?
middle-age
