HISTO: Bone tumours Flashcards
List 3 benign bone forming tumours.
Osteoid osteoma
Osteoblastoma
Osteoma
List 3 benign cartilaginous differentiation tumours.
Osteochondroma - pedunculated
Enchondroma - hands/feet
Chondroblastoma
Which syndrome is associated with fibrous dysplasia?
McCune Albright - cafe au lait and endocrine problems and fibrous dysplasia
What mutation is seen in fibrous dysplasia?
GNAS
What is “soap bubble osteolysis” a feature of?
Fibrous dysplasia
What is “chinese letters” bone biopsy associated with?
Fibrous dysplasia - rounded and curved trabeular bone and marrow replaced by fibrous stroma
What is “shepherd’s crook deformity” characteristic of?
Fibrous dysplasia
How do osteochondromas present?
Pedunculated - have a cartilaginous surface, mimic tubular bone
What is “popcorn calcification” characteristic of?
Enchondroma
Where do giant cell tumours usually occur?
Epiphyses but extend to metaphysis, mostly females
Where do chondroblastomas usually occur?
Ends of long bones
What are “lytic lesions, with osteoclasts on background of spindle/ovoid cells” characteristic of?
Giant cell tumour
Which benign bone tumour can be locally aggressive?
Giant cell tumour (borderline malignant)
What are the “giant” cells in giant cell tumours?
Osteoclasts
What are 3 primary malignant bone tumours?
Osteosarcoma
Chondrosarcoma
Ewin’s/PTEN
What is “Codman’s triangle” characteristic of?
Osteosarcoma
Which tumour is made of malignant mesenchymal cells +/- bone/cartilage?
Osteosarcoma
What is the red cytoplasm of osteosarcoma cells positive for?
ALP
Compare the prognosis of the primary malignant bone tumours.
Osteosarcoma - 60% 5yr survival - adolescent
Chondrosarcoma - 70% 5yr survival - adult >40yrs
Ewing’s - 75% 5y survival - adolescents
Which malignant bone tumour usually affects the proximal skeleton?
Chondrosarcoma
What tumour has XR of bone that is “lytic with fluffy calcification”?
Chondrosarcoma
What type of cells are seen in Ewing’s?
Small round cell tumour
What tumour has XR of bone that shows “onion skinning of the periosteum”?
Ewing’s
What mutation is seen in Ewing’s?
11:22 (EWS/Fli1)
What is characteristic of Ewing’s on immunostaning?
Synaptophysin and S100 may be positive (these are also positive in neuroblastomas)
CD99
Name 3 soft tissue tumours.
Liposarcoma/myxoid
Pleiomorphic
Spindle cell tumour
Why are synovial sarcomas “biphasic” tumours?
They have epithelial and spindle cell areas
What are the good prognostic factors for a soft tissue tumour?
<5cm, superficial to deep fascia, diploid, low proliferation and tumour suppressor gene present
Which tumours are poorly vascularised and so bad for chemotherapy?
Osteosarcoma
What are giant cell granulomas also known as?
Reparative tumours
What is the most common type of bone tumour overall?
Metastatic
