MSK 424 - 428 Flashcards
explain why estrogen is bone protective
estrogen blocks apoptosis in bone forming osteoblast and induces apoptosis in bone-resorbing osteoclast
what bone cell secretes acid and collagenases?
osteoclast
what cell is multinucleated and is derived from monocyte?
osteoclast
what bone path takes place in epiphysis?
Giant cell tumor
what bone paths take place in metaphysis?
osteosarcoma, osteochondroma
what bone paths take place in diaphysis?
Ewing sarcoma, myeloma, osteoid osteoma
which bone path is associated with nighttime pain, central nidus, and pain released by aspirin?
osteoid osteoma
3 characteristics of Ewing sarcoma?
- anaplastic small blue cell malignant tumor
- extremely aggressive with early metastases, but responsive to chemotherapy
- “onion skin” periosteal reaction in bone
what population is most affected by Ewing sarcoma?
boys
what is the 2nd most common primary malignant tumor after multiple myeloma?
osteosarcoma (osteogenic sarcoma)
name 5 predisposing factors for osteosarcoma (osteogenic sarcoma)
- paget dz of bone
- bone infarcts
- radiation
- familial retinoblastoma
- Li Fraumeni syndrome (germline p53 mutation)
what is the age distribution who get osteosarcoma?
biomodal distribution (10-20 yr old and more than 65)
what other malignancy has also bimodal distribution?
hodgkin (young adulthood and more than 55)
on x-ray, how will osteosarcoma look like?
codman triangle (from elevation of periosteum) or sunburst pattern on x-ray
what is the most common benign tumor?
osteochondroma
does osteochondroma transform to chondrosarcoma?
rarely yes
what is the characteristic of osteochondroma?
mature bone with cartilagionus (chondroid) cap
what bone tumor is characterized as soap bubble appearance on x-ray with multinucleated giant cells
giant cell tumor
what is the most common site of giant cell tumor?
epiphyseal end of long bone around knee
in paget dz of bone, hearing loss is due to
auditory foramen narrowing
name the 4 stages of paget dz of bone
- lytic (osteoclast)
- mixed (osteoclast + osteoblast)
- sclerotic (osteoblast)
- quiescent (minimal osteoclast/osteoblast)