Key clinical point: An inverse association was observed between preexisting type 2 diabetes (T2DM) and prostate cancer across the duration of T2DM and all types of medications for T2DM.
Major finding: Overall, men with T2DM had a lower risk for prostate cancer (odds ratio, 0.81; 95% confidence interval, 0.78-0.84) than those without T2DM and this inverse association remained consistent across the duration of T2DM. The inverse association was also found for all medication types, including insulin, metformin, and sulfonylurea, compared to men without T2DM.
Study details: The data come from a Swedish matched case-control study which included 31,415 men with prostate cancer and 154,812 without prostate cancer.
Disclosures: This study was supported by the Swedish Research Council, the Swedish Cancer Society, and the Stockholm Cancer Society. B Zethelius is an employee of the Swedish Medical Products Agency. H Garmo, M Van Hemelrijck, J Adolfsson, P Stattin, and B Zethelius declared no conflicts of interest.
“Type 2 diabetes has been associated with a decreased risk of prostate cancer in several studies. One hypothesis is that antidiabetic medication may underly this observation. Antidiabetic medications, such as metformin, are under study as chemoprevention agents. Lin et al. conducted a case-control study of men with or without prostate cancer to further evaluate the association of type 2 diabetes and prostate cancer risk. A decreased risk of prostate cancer was observed for men with type 2 diabetes; however, when evaluated by risk category, the risk of prostate cancer was decreased for those with low or intermediate risk disease, but not for those with high risk disease. When evaluated by antidiabetic medication type, the decreased risk of diagnosis occurred in those receiving insulin, metformin, and sulfonylureas. While not all confounders were accounted for in this study, the findings do warrant further study of these agents in prostate cancer.”
Mark Klein, MD
E Lin et al. BMC Cancer. 2020 Jun 15. doi: 10.1186/s12885-020-07036-4.