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What is Onion skin periosteal reaction is usually seen in: and explain in detail?
Ewing sarcoma Destructive lesion in the diaphysis of a long bone with an "onion skin" periosteal reaction. Originates in the metaphysis of a long bone, but frequently extends for a considerable distance into the diaphysis. Classically, PNET class of tumour, with c-myc positive,having round cells is histology. -Osteosarcoma show codman's triangle, sunray or sunburst appearance as periosteal reaction