Real-world experiences in patients with Ewing sarcoma treated at a specialist centre in Turkey.

Objectives: The present study evaluates the clinical outcomes of children, adolescents and adults with Ewing sarcoma and identifies the prognostic factors. Methods: Included in the study were 222 pediatric and adult patients diagnosed with Ewing sarcoma (EwS) who were followed up between 1992 and 2019, and whose data were analyzed retrospectively. Results: The median age of 131 male and 91 female patients included in the study was 13 (1-64). The median follow-up duration of the survivors was 79 months (range, 11-182 months). The 3-year EFS rate of the 222 patients was 34 % (Confidence Interval (CI) (0.158-0.242 %) and the OS rate was 54 % (CI, 0.289-0.590 %). For the non-metastatic patients, the 3-year EFS rate was 47 % and the OS was 68 %, while for the metastatic patients the 3-year EFS rate was 13 % and the OS was 30 %. Of the patient sample, 81 (36, 5 %) survived, of whom 72 were continuously free of disease while the disease persisted in nine, and three developed a secondary neoplasm (2 of whom subsequently died while one survived disease-free). Of the 129 patients who relapsed with metastases and/or local recurrence, eight survived and are disease-free, nine are alive with uncontrolled disease; five were lost to follow-up and 107 died. Conclusion: The findings of the present study suggest metastatic disease at presentation and positive margins after surgery to be of prognostic significance in EwS. Disruptions in aggressive local treatments may reduce the chances of cure in EwS.