Distribution and Surgical Management of Visceral Ewing Sarcoma Among Children and Adolescents.

ABSTRACT

INTRODUCTION: Ewing sarcoma (EWS) is a highly malignant tumor of bone and soft tissue that occasionally arises from viscera. Visceral EWS (V-EWS) is challenging to manage given its varied organ distribution and often late-stage presentation. We aimed to characterize our institutional experience with V-EWS, focusing on its surgical management, and to compare V-EWS outcomes against those with osseous (O-EWS) and soft tissue EWS (ST-EWS). METHODS: Retrospective review of all EWS patients ≤21 years presenting to a single institution between 2000 and 2022. Patient- and disease-specific characteristics were compared. Overall and relapse-free survival were estimated using Kaplan Meier methods and log-rank test. RESULTS: 156 EWS patients were identified 117 O-EWS, 20 ST-EWS, and 19 V-EWS. V-EWS arose in the kidney (n = 5), lung (n = 5), intestine (n = 2), esophagus (n = 1), liver (n = 1), pancreas (n = 1), adrenal gland (n = 1), vagina (n = 1), brain (n = 1), and spinal cord (n = 1). No significant demographic differences were detected between EWS groups. V-EWS was more frequently metastatic at presentation (63.2%; p = 0.005), yet no significant overall or relapse-free survival differences emerged between EWS groups, with similar follow-up intervals. While V-EWS required multiple unique operative strategies to gain primary control, no significant difference in treatment strategies appeared between groups. Surgery-only primary control was associated with improved overall and relapse-free survival in all groups. CONCLUSIONS: V-EWS presents unique management challenges in children and adolescents given its variable sites of origin. This large cohort is the first to describe the surgical management and outcomes of V-EWS, demonstrating more frequent metastatic presentation, while achieving similar survival across groups. LEVEL OF EVIDENCE Level 2 - Cohort Study.