Safety of Fertility-Sparing Surgery in Young Women with Stage I Endometrioid Epithelial and Mucinous Ovarian Cancer: A Population-Based Analysis

Introduction: The aim of this study was to assess the safety of fertility-sparing surgery (FSS) in stage I endometrioid epithelial cancer (EEOC) and mucinous ovarian cancer (MOC).Methods: A retrospective case-controlled study was conducted using the Surveillance, Epidemiology, and End Results (SEER) database, focusing on stage I EEOC and MOC between 2000 and 2016. The effects of FSS on overall survival (OS) were compared using log-rank tests. Univariate and multivariate Cox analyses were performed to control for confounders.Results: The study identified 970 patients with FIGO stage I EEOC and 810 with stage I MOC. Of these patients, 116 (12.0%) EEOC and 268 (33.1%) MOC patients underwent fertility-sparing surgery. The results showed that patients with G3 EEOC had a worse 5-year OS than patients with G1 EEOC (96.1% vs. 90.1%, p = 0.020). IC stage MOC patients had a worse prognosis than IA and IB stage patients (94.9% vs. 88.7%, p = 0.001). FSS did not significantly affect the 5-year OS of patients with EEOC (94.8% vs. 95.4%, p = 0.687) or MOC (95.9% vs. 92.3%, p = 0.071). Further subgroup analysis according to tumor stage and histological grade did not show a worse OS with FSS in stage I EEOC or MOC patients, even with high-risk types such as G3 histology and IC phase. In a multivariable analysis, the application of FSS was not associated with inferior OS in EEOC or MOC.Conclusions: FSS for patients with stage I EEOC or MOC does not lead to worse outcomes than radical surgery, making it a viable option for young patients with early-stage disease wishing to preserve fertility.