Oncological and Reproductive Outcomes of a Standardized Hysteroscopic Approach for the Fertility-Sparing Treatment of Atypical Endometrial Hyperplasia and Early-Stage Endometrial Cancer

Background/Objectives: Fertility-sparing treatment (FST) is an accepted option for selected women with atypical endometrial hyperplasia (AEH) and early-stage endometrioid endometrial cancer (EC). While combined progestin therapy and hysteroscopic approaches yield the best outcomes, the surgical component has long lacked standardization. This study aimed to evaluate oncological and reproductive outcomes following a standardized hysteroscopic fertility-sparing approach. Methods: This retrospective single-center study included women of reproductive age diagnosed with AEH or grade 1–2 endometrioid EC between 2021 and 2024 at the Digital Hysteroscopic Clinic CLASS Hysteroscopy, Fondazione Policlinico A. Gemelli IRCCS, Rome. All patients were treated using a standardized hysteroscopic approach based on lesion type and disease extension, combined with progestin therapy. Oncological outcomes included complete response (CR), time to CR and recurrence. Reproductive outcomes included the clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate (MR). Multivariate analysis was performed to identify factors associated with CR and relapse. Results: A total of 138 patients were included (79 AEH, 59 EC). CR rates were high and comparable between AEH (94.9%) and EC (98.2%), with a median time to response of 6 months. Recurrence rates did not differ significantly between groups (16.7% AEH vs. 26.8% EC). CPR was similar (47.5% AEH vs. 54.8% EC), with LBR exceeding 50% among women who conceived. Multivariate analysis identified age ≥ 35 years as the only factor associated with reduced response and increased relapse risk. Conclusions: A standardized hysteroscopic fertility-sparing approach combined with progestin therapy provides excellent oncologic control and favorable reproductive outcomes. Lesion severity did not affect outcomes when hysteroscopic removal was adequately performed, while patient age remains a key determinant of outcomes.