???? ??? ?? ?? ? ????? ? ?? ??? ?? ???? ??? ??? ? ??? ? ??? ? ?? ? ??? ??? ??????.????? ? ?? ???? ??? ??? ???? ????? ??? ????? ???? ?????? ???? ?? ?? ????? ???? ? ?? ??? ?????????. ?????.About 87 % of Ewing sarcomas are Ewing sarcoma of bone, which can be a bone tumor that usually occurs within the thigh bones (femurs), pelvis, ribs, or shoulder bl