RESUMO
PURPOSE: The purpose of this study was to present treatment results of childhood Ewing's sarcoma (ES) of the bone in Serbia and to analyze prognostic factors. METHODS: We performed a detailed analysis on a series of 107 patients with ES of the bone treated at the Institute for Oncology and Radiology of Serbia between 2000 and 2014, using modern multimodal therapy. RESULTS: Median age at the time of diagnosis was 14 years, with 56.07% of the patients being ≤14 years. There was a male predominance (59.81%). The most common primary sites were pelvis (25.23%), femur (17.76%) and tibia (12.15%). Thirty-four patients (31.78%) had metastatic disease, 17 of which had isolated lung metastases, 9 bone metastases and 8 patients had both. Tumor size ≤ 8 cm had 38.32% and >8 cm had 61.68% patients. Overall, 51.4% patients underwent surgery and radiotherapy as a local treatment modality after neoadjuvant chemotherapy. Radiotherapy alone was performed in 24 patients. The 5-year overall survival (OS) was 43.8%. For patients with localized disease, the 5-year OS was 56.4% and for patients with metastatic disease 17.6%. In patients with initially nonmetastatic disease, age under 14 years, with tumor size <8 cm and a good response to the neoadjuvant chemotherapy, the OS correlated with better outcome. CONCLUSIONS: Modern multidisciplinary approach in treatment of childhood ES of the bone in accordance with the recommended pediatric protocols, gives good treatment results. Therapy should be performed in referral centers.