Is there a link between type 2 diabetes and endometrial cancer in the research?

Type 2 diabetes (T2D) and endometrial cancer share several risk factors, and research has explored whether having T2D directly increases the chance of developing endometrial cancer. The short answer is yes: multiple studies have found a link, though the relationship is complex and partly tied to obesity. This page explains what the research shows about the connection and possible reasons behind it.

What the research says

A 2025 systematic review and meta-analysis of Mendelian randomization studies found that T2D is significantly associated with an increased risk of endometrial cancer (odds ratio 1.07, 95% CI: 1.04-1.09) ⁶. This means people with T2D have about a 7% higher odds of developing endometrial cancer compared to those without T2D, based on genetic evidence. Another review from 2021 highlights that the link is strongest for endometrial cancer among gynecologic cancers, and that obesity, T2D, and cancer interact in complex ways ¹⁰. An earlier overview from 2018 notes that while a higher risk of endometrial cancer is seen in T2D, this association is largely reduced after adjusting for obesity, suggesting that obesity plays a major role ¹¹. The same review points to insulin resistance, chronic inflammation, and high levels of free ovarian steroid hormones as possible mechanisms ¹¹. Additionally, a 2024 review on PCOS, which is closely linked to T2D, mentions that PCOS increases risks of metabolic syndrome, T2D, and endometrial cancer, further supporting the connection ⁹.

What to ask your doctor

• Given my type 2 diabetes, what is my personal risk for endometrial cancer?
• How does my weight or body mass index affect my risk, and what steps can I take to lower it?
• Are there any screening tests for endometrial cancer that I should consider?
• Could my diabetes medications influence my cancer risk?
• What symptoms of endometrial cancer should I watch for, such as unusual bleeding?