Thus, surgery is chosen as definitive local therapy for suitable patients, but radiation therapy is appropriate for patients with unresectable disease or those who would experience functional compromise by definitive surgery. The possibility of impaired function needs to be measured against the possibility of second tumors in the radiation field (see below). Adjuvant radiation therapy should be considered for patients with residual microscopic disease, inadequate margins, or who have viable tumor in the resected specimen and close margins.
When preoperative assessment has suggested a high probability that surgical margins will be close or positive, preoperative radiation therapy has achieved tumor shrinkage and allowed surgical resection with clear margins.
High-Dose Therapy With Stem Cell Rescue for Ewing Sarcoma
For patients with a high risk of relapse with conventional treatments, certain investigators have utilized high-dose chemotherapy with hematopoietic stem cell transplant (HSCT) as consolidation treatment, in an effort to improve outcome.[23,24,25,26,27,28,29,30,31,32,33,34] In a prospective study, patients with bone and/or bone marrow metastases at diagnosis were treated with aggressive chemotherapy, surgery, and/or radiation and HSCT if a good initial response was achieved. The study showed no benefit for HSCT compared with historical controls. A retrospective review using international bone marrow transplant registries compared outcome after treatment with reduced-intensity conditioning to high-intensity conditioning followed by allogeneic stem cell transplant for patients with Ewing sarcoma at high risk for relapse.[Level of evidence: 3iiiA] There was no difference in outcome and the authors concluded that this suggested the absence of a clinically relevant graft-versus-tumor effect against Ewing sarcoma tumor cells with current approaches. Multiple small studies that report benefit for HSCT have been published but are difficult to interpret because only patients who have a good initial response to standard chemotherapy are considered for HSCT. The role of high-dose therapy followed by stem cell rescue is being investigated in a Euro-Ewing clinical trial (EURO-EWING-INTERGROUP-EE99) for patients that present with pulmonary metastases.
Ewing Sarcoma/Specific Sites
Separate journal articles have been written that discuss diagnostic findings, treatment, and outcome of patients with bone lesions at the following sites:
- Hand and foot.[43,44]
- Chest wall/rib.[45,46,47,48]
- Head and neck.