Ewing 's sarcoma is a type of bone cancer . Antisense oligodeoxynucleotides have been proposed as possible treatment by down-regulating the expression of the oncogenic fusion protein associated with the development of Ewing sarcoma resulting from the EWS-ETS gene translocation . In addition , the synthetic retinoid derivative fenretinide ( 4-hydroxy ( phenyl ) retinamide ) has been reported to induce high levels of cell death in Ewing sarcoma cell lines in vitro and to delay growth of Ewing sarcoma xenografts in vivo mouse models .