Bone cancer Flashcards
What are 3 histological patterns of bone destruction?
- Geographic: lesion has a clearly defined margin
- Moth-eaten: larger holes of various sizes
- Permeative: ill-defined, diffuse, subtle appearance
What is the term for a small benign bone tumour usually seen in male children/adolescents?
Osteoid osteoma
Where do osteoid osteomas usually form?
Midshaft of femur
What is the cell lineage of an osteoid osteoma?
Mesoderm > Fibroblasts > Osteoblasts > Osteoid osteoma
What is the most common symtom of an osteoid osteoma?
Localized, increasing, severe pain in the lower leg
How does an osteoid osteoma appear on CT scan?
Tumour core (nidus): osteoid tissue containing osteoblasts, osteoclasts, granulation tissue, nest-like appearance
Shell of dense, reactive, new bone
What is the prognosis of osteoid osteoma?
Excellent: cannot become malignant
What is the term for a highly malignant tumour of osteoblasts and neoplastic bone?
Osteosarcoma
How common is osteosarcoma?
Most common type of malignant primary bone tumour
(which is still rare, because primary bone tumours are rare)
What demographics are commonly affected by osteosarcoma?
Males
Young people (10-25 yrs)
Old people (>60 yrs)
What comorbidity may predispose an individual to osteosarcoma?
Paget’s disease
What are 3 common places where osteosarcoma may be found?
- Knee
- Vertebrae
- Pelvis
Why does osteosarcoma increase a patient’s risk for fracture?
Tumour destroys bone cortex
What is the cell lineage of an osteosarcoma?
Mesoderm > Fibroblasts > Osteoblasts > Osteosarcoma
What is the histological appearance of an osteosarcoma?
Pleomorphic cells mixed with new bone
What is the term for a commonly benign tumour of giant osteoclasts causing extensive bone resorption?
Giant cell tumour (osteoclastoma)