Management and outcome of extraosseous ewing's sarcoma family tumors treated at a tertiary care center in North East India: A retrospective analysis

Introduction: Extraosseous Ewing's Sarcoma is rare, aggressive malignant soft-tissue tumors treated similar to Ewing's sarcoma of bone. This study evaluates the clinicopathological pattern, treatment and outcomes of localized extraosseous Ewing's sarcoma family tumors (ESFTs) treated with an uniform treatment regimen. Materials and Methods: This is a retrospective single institution study where we evaluated the hospital records of localized extraosseous ESFT treated between January 2011 and December 2018. Fifteen patients were found eligible for analysis. Patient demographics, management details, and outcomes were analyzed statistically. Time to event was measured from the date of diagnosis and survival curves were estimated by Kaplan–Meier method with Log-rank test for comparison. Results: The median follow-up of the cohort was 17 months (range: 3–81 months). The mean age of patients was 14.4 years and the average tumor size was 9.92 cm. Two-thirds of the patients received definitive radiotherapy as the local treatment with 93.3% patients receiving induction chemotherapy. The 5-year local control rate, progression-free survival, and overall survival (OS) were 80%, 53.3%, and 46.7%, respectively. On univariate analysis, tumor size