????? ??? ?? ?? ?? ? ?? ??? ?? ???? , ?? ??? ????? ??? ?? ?? ?? ????? ??? ?? ?? ?? ???? ?? ??? ?? ??? ??? ?? ??? ? ??? ??? ?? ????.????? ? ?? ???? ??? ??? ???? ????? ??? ????? ???? ?????? ???? ?? ?? ????? ???? ? ?? ??? ?????????. ?????.Roughly 87 percent of Ewing sarcomas are Ewing sarcoma of bone, that's a bone tumor that sometimes happens while i