Factors that Impact the Outcomes in Ewing's Sarcoma: Experience from a Regional Cancer Center in Southern India.

Ewing's sarcoma family of tumors (EWSFT) is common in the second decade of life. Achieving good outcomes in EWSFT requires a multimodality approach. We report the clinico-pathological features, treatment, and survival outcomes of patients with EWSFT treated at our center. Patients diagnosed and treated for EWSFT at our center from 2009-2017 were included in this study. Data was collected from the patient's case records. Event-free survival (EFS) and overall survival (OS) were estimated using the Kaplan-Meier method. The study included 173 patients among whom 44 (25%) patients were metastatic at diagnosis. The median age of patients was 16 years. The most common site of the primary tumor was the pelvis (16.1%), followed by long bones. The median follow-up was 75 months and the 5-year EFS and OS were 43.7% and 45.1% respectively for the overall cohort whereas for the localized disease were 56.6% and 57.2% respectively. Metastatic disease, tumor volume > 200 ml, tumor diameter > 8 cm, pelvic site, hemoglobin < 10 gms%, elevated lactate dehydrogenase, positive margin, and necrosis less than 90% were significantly associated with inferior OS on univariate analysis. On multivariate analysis, metastasis disease, tumor diameter > 8 cm, and necrosis < 90% were significantly associated with inferior OS. Large tumors, advanced disease, and poor response to chemotherapy are associated with poor outcomes in EWSFT. Whether the use of dose-dense chemotherapy and/or autologous stem cell transplant would improve outcomes without increased toxicity in resource-limited settings needs to be explored. Supplementary Information: The online version contains supplementary material available at 10.1007/s13193-023-01817-6.