Bariatric surgery improved efficacy of fertility-sparing treatment in obese women with endometrial cancer or atypical hyperplasia: a retrospective cohort study

The effectiveness of fertility-sparing treatment (FST) for endometrial cancer (EC) and atypical endometrial hyperplasia (AEH) is less than ideal in obese women. This study aimed to assess bariatric surgery (BS) as an adjunctive intervention to enhance oncologic outcomes in this high-risk population. We conducted a retrospective cohort study of 25 morbidly obese women with EC or AEH undergoing FST between 2022 and 2024. Survival analysis indicated a tendency of improvement in a cumulative complete remission (CR) rate in the BS group compared with the non-BS group (p=0.053). After adjusting for pathology, BS was identified as a strong independent predictor of achieving CR (HR = 7.82; 95% CI: 1.81–33.78; p=0.006). Compared to the non-BS group, patients who underwent BS also demonstrated significant improvements in metabolic profiles (reduced BMI, HbA1c, fasting insulin), a decrease in systemic inflammation (lower IL-6, neutrophils), and enhanced antitumor immunity (increased circulating CD8⁺ T and NK cells). Furthermore, the tumor proliferation marker Ki-67 was significantly reduced in the BS group (p=0.03). Correlation network connected obesity-related metabolic dysfunction with pro-inflammatory and tumor-proliferative pathways. BS may serve as a superior intervention for weight loss in morbidly obese EC patients undergoing FST, likely by modulating metabolic, inflammatory, and immune pathways.