Background. Primary Ewing sarcoma (ES) can sometimes present as a chest-wall tumor. Multidisciplinary management, including chemotherapy and local treatment consisting of surgery, radiotherapy (RT), or both, has improved the survival of patients with localized ES; however, the best approach to achieving local control remains controversial.Methods. We retrospectively analyzed data from 198 patients with non-metastatic ES of the chest wall, who were registered in the database of the German Society of Pediatric Hematology and Oncology between July 1998 and April 2009. The majority of patients (n = 130) presented with rib tumors; 7 patients received RT only, 85 patients underwent surgery alone, and 106 patients were treated with a combination of surgery and RT. Results. Overall survival in all patients was 78 and 71 % at 3 and 5 years, respectively. Event-free survival at 5 years (5-year EFS) was 57 % in the RT group, 73 % in the surgery group and 63 % in the surgery ? RT group. In patients with complete resections, 5-year EFS did not improve with the addition of RT compared with surgery alone. There was no difference in the 5-year EFS in patients with partial (63 %) or total (64 %) resection of the affected ribs, and median follow-up was 4.71 years (range 0.40-13.48). Conclusions. Complete tumor resection is the best way to achieve local control of ES of the chest wall; additional RT is only useful in patients with incomplete resection. The main limitation of this study was its retrospective nature, and the benefit of total resection of the affected ribs could not be proved.Ewing sarcoma (ES) is a rare, highly malignant disease found in children, adolescents, and young adults, with a reported incidence of three persons per million people per year within a Caucasian population. Median age at diagnosis is 15 years, 1 and the chest wall is the primary site of presentation in 14 % of patients. The tumor most commonly originates from osseous structures (ribs 9 %, scapula 4 %, clavicle 1 %, or sternum \1 %), and even less frequently from the soft tissue of the chest wall (\1 %). 2 ESs of the chest wall have also been referred to as Askin's tumors, 3 until an identical molecular signature revealed a common origin.Multidisciplinary management has improved the 5-year survival of patients with localized disease to rates of 60-70 % and higher. 4-6 Multimodal therapy includes systemic therapy as well as surgery and radiotherapy (RT). 7 Until now, clinical trials on ES have principally focused on a comprehensive investigation of systemic treatment. 8-10 Although multi-agent chemotherapy is well defined as the standard of care for ES patients, the best approach for local control of ES of the chest wall remains a matter of discussion. 11 Local treatment of chest-wall tumors is often challenging, especially in young patients, as both local treatment modalities (surgery and RT) may be associated with significant long-term sequelae. 12 Due to the rarity of ES of the chest wall, only a limited number of patient series have been publis...