These drugs are usually given once every month or once every 3 months, but they may be given more often. Bone metastases are much more common than primary bone cancer. Such an approach will result in local control of the tumor with acceptable morbidity in most patients. Sometimes metastases develop in several bones at the same time. Treatment Option Overview for Ewing Sarcoma Revised text to state that adjuvant radiation therapy should be considered for patients with residual microscopic disease or inadequate margins. Several potential chimeric antigen receptors target antigens that have been identified for Ewing sarcomas.