Ewing sarcoma in adults treated with modern radiotherapy techniques

Background and purpose: To evaluate local control and survival outcomes in adults with Ewing sarcoma (ES) treated with radiotherapy (RT). Material and methods: Retrospective review of all 109 patients age >= 18 treated for ES with RT to the primary site at Memorial Sloan Kettering Cancer Center between 1990 and 2011. RT was used as the definitive local control modality in 44% of patients, preoperatively for 6%, and postoperatively for 50%. Results: Median age at diagnosis was 27 years (range, 18-67). The 5-year local failure (LF) was 18%. Differences in LF were not identified when evaluated by modality of local control (RT versus combined surgery and RT), RT dose, fractionation, and RT technique. However, margin status at time of resection significantly predicted LF. The 5-year event-free survival and overall survival rates were 44% and 66% for patients with localized disease, compared with 16% and 26% for metastatic disease (p = 0.0005 and 0.0002). Tumor size, histopathologic response to chemotherapy, and treatment on or according to a protocol were also significantly associated with survival. Conclusions: This series of adults treated with modern chemotherapy and RT had prognostic factors and outcomes similar to adolescents with ES. All adults with ES should be treated with an aggressive, multidisciplinary approach. (C) 2014 Published by Elsevier Ireland Ltd.