Tirzepatide linked to lower short-term endometrial cancer risk in large cohort study

Women with overweight or obesity who started taking tirzepatide were less likely to receive a new endometrial cancer diagnosis over two years than comparable women who pursued lifestyle modification, according to a retrospective cohort study published in Diabetology & Metabolic Syndrome. Using the TriNetX US Collaborative Network, researchers identified women with overweight or obesity who initiated either tirzepatide or lifestyle modification interventions between January 1, 2022, and December 31, 2025. After 1:1 propensity score matching, 176,981 patients were included in each group, creating two cohorts balanced on measured baseline characteristics.

The matched cohorts were closely aligned in age, with a mean of 49.3 ± 13.8 years in the tirzepatide group and 49.1 ± 16.1 years in the lifestyle modification group. The estimated cumulative follow-up was approximately 202,632 person-years in the tirzepatide group and 194,447 person-years in the comparator group. Over a maximum follow-up window of two years, tirzepatide use was associated with a lower hazard of newly recorded endometrial cancer diagnoses compared with lifestyle modification, with a hazard ratio of 0.717 and a 95% confidence interval of 0.593 to 0.867. The association was consistent across most of the subgroups examined, including women aged 50 years or older, White women, and women with type 2 diabetes, hypertension, hyperlipidemia, or obstructive sleep apnea.

The study’s rationale rests on two established observations. Endometrial cancer is strongly associated with obesity, and tirzepatide produces substantial weight loss. Whether any of these mechanisms explains the observed difference in diagnoses cannot be determined from this study design, which measured recorded diagnoses rather than confirmed biological outcomes.

The authors are careful about interpretation. In their conclusion, they state that tirzepatide use was associated with a lower short-term hazard of newly recorded endometrial cancer diagnoses among women with overweight or obesity, but that these observational findings do not establish a preventive effect, and longer-term studies are needed to assess whether the association persists. As a retrospective analysis of electronic health records rather than a randomized trial, the study cannot rule out residual confounding, and the two-year window captures only short-term outcomes. The article was published on October 13, 2026, as an open-access research paper, and the version shared at publication is subject to further edits before the final Version of Record.

Subject of Research: The association between tirzepatide use and endometrial cancer risk in women with overweight or obesity

Article Title: Tirzepatide use and the risk of endometrial cancer in women with overweight or obesity: a retrospective cohort study

Article References: Kao, P.-N., Lai, C.-C., & Wu, J.-Y. (2026). Tirzepatide use and the risk of endometrial cancer in women with overweight or obesity: a retrospective cohort study. Diabetology & Metabolic Syndrome. https://doi.org/10.1186/s13098-026-02329-3

Image Credits: AI Generated

DOI: 10.1186/s13098-026-02329-3

Keywords: tirzepatide, endometrial cancer, obesity, overweight, retrospective cohort study, TriNetX, propensity score matching, hazard ratio, weight loss, Diabetology & Metabolic Syndrome, risk, endometrial