

THURSDAY, June 4, 2026 (HealthDay News) -- Glucagon-like peptide-1 receptor agonist (GLP-1 RA) exposure is associated with a lower incidence of breast cancer, according to a study published online June 2 in JCO Oncology Practice to coincide with the annual meeting of the American Society of Clinical Oncology, held from May 29 to June 2 in Chicago.
Elizabeth S. McDonald, M.D., Ph.D., from the Perelman School of Medicine at the University of Pennsylvania in Philadelphia, and colleagues examined the impact of GLP-1 RAs on breast cancer risk in a retrospective cohort study involving 111,646 women aged 45 to 80 years with a body mass index (BMI) ≥25 kg/m2 and a documented imaging outcome. One-to-one, case-control matching using propensity scores was performed based on age, race, ethnicity, highest BMI, breast density, and history of type 2 diabetes.
The researchers found that the incidence of breast cancer was lower in association with GLP-1 RA exposure (odds ratio, 0.649). GLP-1 RA exposure was associated with a lower breast cancer incidence in the matched logistic regression with 30,528 observations (600 cancer cases; odds ratio, 0.695).
"While our study was observational and does not definitively confirm an association between GLP-1 medications and reduced breast cancer incidence, it does add to the growing body of evidence suggesting that it's worth investigating these weight-loss drugs as potential cancer prevention tools," McDonald said in a statement.