Prognostic Role of Radiotherapy in Low-Grade Endometrial Stromal Sarcoma: A SEER-Based Study

Introduction Low-grade endometrial stromal sarcoma (LG-ESS) is a rare malignant mesenchymal neoplasm for which there is no consensus regarding the role of radiotherapy in treatment. This study aimed to evaluate the prognostic significance of external beam radiotherapy (EBRT) using data from the Surveillance, Epidemiology, and End Results (SEER) database.] Methods This retrospective study evaluated the role of EBRT in 1254 patients with LG-ESS using SEER data (2000-2021). Propensity score matching (PSM) was applied to compare outcomes between EBRT and non-EBRT groups. Cox and competing risk models assessed overall survival (OS) and cancer-specific survival (CSS). Results EBRT showed no survival benefit in either unmatched or matched cohorts. Post-PSM, OS (HR = 1.21, 95% CI 0.61-2.39) and CSS (HR = 1.75, 95% CI 0.69-4.43) remained unaffected by EBRT (P > 0.05). Lymphadenectomy and bilateral salpingectomy and oophorectomy (BSO) also demonstrated no significant associations with survival outcomes. Key prognostic factors included older age, larger tumor size, advanced stage, and chemotherapy use, all linked to poorer OS and CSS. Conclusion EBRT, lymphadenectomy, and BSO do not offer significant survival benefits for patients with LG-ESS. Prognosis was independently influenced by age, tumor size, stage, and chemotherapy use (associated with poorer outcomes). These findings support a more individualized, risk-adapted approach to LG-ESS management and highlight the need for prospective studies to define the optimal role of comprehensive treatment strategies.