Diabetes drugs and the incidence of solid cancers: a survey of the current evidence

ABSTRACT

Introduction: The evaluation of the relationship between the use of antidiabetic drug and the occurrence of cancer is extremely challenging, both from the clinical and pharmacoepidemiological standpoint. This narrative review described the current evidence supporting a relationship between the use of antidiabetic drugs and the incidence of solid cancers.

Areas covered: Data from pharmacoepidemiological studies on cancer incidence were presented for the main antidiabetic drugs and drug classes, including human insulin and insulin analogues, metformin, sulfonylureas, glinides, alpha-glucosidase inhibitors, thiazolidinediones, incretin mimetics, and sodium glucose co-transporter 2 inhibitors. The relationship between the use of antidiabetics and the incidence of solid cancer was described in strata by any cancer and by organ-specific cancer and by drug and by drug classes. Information supporting biological evidence and putative mechanisms were also provided.

Expert opinion: The history of exploration of the relationship between antidiabetic drugs and the risk of solid cancers has showed several issues. Unrecognized biases and misinterpretations of study results have had important consequences that delayed the identification of actual risk and benefits of the use of antidiabetic drugs associated with cancer occurrence or progression. The lesson learned from the past should address the future research in this area, since in the majority of cases findings are controversial and confirmatory studies are warranted.

KEYWORDS:

• Diabetes
• antidiabetic drugs
• solid cancer
• pharmacoepidemiological studies
• chemoprevention

Article highlights

• The relationship between the exposure to antidiabetic drugs and the incidence of solid cancer was explored in many observational studies. Unfortunately, these studies are easily subjected to bias and often provided misleading results.

• In the majority of cases, the current evidence is controversial and good quality observational studies are required. With very few exceptions, a cancerogenic effect of antidiabetic drugs seems unlikely as well as a chemopreventive activity, and the benefit-risk profile of these drugs remained favorable.

• Caution should be recommended in the conduction of future studies, particularly when designing the study, interpreting their results, and taking consequent regulatory decision.

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Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Additional information

Funding

This paper has not been funded.