Diabetes and endometrial cancer: An Italian case-control study

We considered the association between diabetes and risk of endometrial canc er using data from a large case-control study conducted in Italy. Cases wer e 752 women with incident, histologically confirmed endometrial cancer <75 years of age (median age 60 years, range 28-74) admitted to a network of ho spitals in Milan. Controls were 2,606 patients (median age 54 years, range 25-74) aged < 75 years, admitted for acute non-neoplastic, non-gynecologica l, non-hormone-related conditions to the same network of hospitals where ca ses had been identified. A total of 132 (17.6%) cases and 116 controls (4.5 %) reported a history of diabetes. The corresponding multivariate odds rati o (OR) was 2.9 [95% confidence interval (CI) 2.2-3.9]. No association emerg ed with diabetes diagnosed under age 40 (likely to be insulin-dependent dia betes), whereas the OR of endometrial cancer was 3.1 (95% CI 2.3-4.2) for d iabetes diagnosed at age greater than or equal to 40 years. The OR of endom etrial cancer in women with history of diabetes was 3.0 for women with a bo dy mass index (BMI) (QI) kg/m(2) <25, 3.6 for those with a BMI of 25-29, an d 3.3 for those with a BMI greater than or equal to 30. No consistent inter action or modifying effect was observed for any other covariate. Our result s confirm that non-insulin-dependent diabetes is associated with the risk o f endometrial cancer. The association may be mediated through elevated oest rogen levels in diabetic women, hyperinsulinemia or insulin-like growth fac tor-1 (IGF-I). (C) 1999 Wiley-Liss, Inc.