Abstract PD8-08: Glp-1 receptor agonists are associated with improved breast cancer outcomes in dcis patients on hormonal therapy: a real-world cohort study

Abstract Background: Ductal carcinoma in situ (DCIS) is a non-invasive breast neoplasm that carries a risk of progression to invasive and metastatic disease. The potential impact of glucagon-like peptide-1 (GLP-1) receptor agonists, commonly used in diabetes management, on breast cancer outcomes in DCIS patients receiving hormonal therapy remains unclear. Methods: Using the TriNetX Research Network, we conducted a retrospective cohort study comparing patients with DCIS on hormonal therapy with (Cohort 1, n=3,049) and without (Cohort 2, n=3,049) concomitant GLP-1 agonist use. Cohorts were propensity score matched on demographic, clinical, and laboratory parameters. The primary outcomes were the incidence of invasive and metastatic breast cancer, overall survival, and progression to stage IV disease over a 5-year period. Risk estimates, survival probability, hazard ratios (HR), and associated 95% confidence intervals (CIs) were calculated. Results: GLP-1 agonist use was associated with a significantly reduced risk of invasive and metastatic breast cancer (risk 4.1% vs 10.8%; risk difference -6.6%, 95% CI -7.9% to -5.3%; HR 0.36, 95% CI 0.29-0.44, p