This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
The bone tumor seen in children with characteristic lamellated periosteal reaction with a mottled appearance and extension into soft tissue is which of the folllowing? 
Select and explain. 
A. Osteosarcoma, B. Giant cell tumor, C. Ewing's sarcoma, D. Osteoid osteoma
C: Ewing's sarcoma
Answer: C: Ewing's sarcoma 
Explanation: Radiologically, Ewing's sarcoma is often associated with a lamellated or "onion peel" periosteal reaction. This appearance is caused by and splitting and thickening of the coex by tumor cells. The lesion is usually lytic and central. Endosteal scalloping is often present. The "onion-peel" appearance is often followed with a "moth-eaten" or mottled appearance and extension into soft tissue.