The Effect of Glucagon‐Like Peptide 1 Receptor Agonists on Peri‐ and Postmenopausal Breast Cancer Outcomes

INTRODUCTION: Studies have shown that obesity increases the risk of postmenopausal breast cancer (BC) by 30%-60% and is associated with poorer outcomes. This is believed to be related to continued exposure to estrogen and prolonged inflammation. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been suggested to significantly lower the risk of several obesity-associated cancers (OACs). We hypothesize that GLP-1RAs can improve outcomes in peri- and postmenopausal BC patients with obesity. METHODS: . We created two cohorts: those who took GLP-1RAs with a Stage I-III BC diagnosis and those who never had exposure to GLP-1RAs. Patients' propensity score was matched based on age, BMI, diabetes, socioeconomic status, and genetic carrier status. Our outcomes of interest were 10-year overall survival (OS) and local recurrence (LR). RESULTS: We identified 10 498 patients who used GLP-1RAs and 93 174 patients who did not. After matching, 19 348 patients were identified, with 9674 per cohort. 10-year OS with the Kaplan-Meier analysis was significantly greater in patients on GLP-1RAs (79%) compared to those not on GLP-1RAs (71%), log-rank test p < 0.0001. The HR for OS was 0.54, 95% CI (0.49-0.60). The risk of LR was significantly lower (HR 0.481, 95% CI (0.425-0.546)). CONCLUSIONS: , GLP-1RA use after diagnosis was associated with improved 10-year OS and lower LR. These findings are hypothesis-generating but suggest a potential therapeutic role for GLP-1RAs, warranting prospective investigation in this high-risk population.