Obesity-Related Cancers Drive the Gap
Obesity-related cancers showed the largest differences, with incidence 45% higher in men and 30% higher in women with T2D in 2010 to 2022, up from 34% and 23% in 1996 to 2009. Colorectal cancer incidence was 17% higher in men and 14% higher in women with T2D, and postmenopausal breast cancer incidence was 8% higher in women with T2D.1
Patterns diverged for cancers not classified as obesity-related. Lung cancer incidence was 23% higher in men and 25% higher in women with T2D in the most recent period; among women, incidence shifted from 12% lower in 1996 to 2009 to 25% higher in 2010 to 2022. Prostate cancer incidence, by contrast, was 19% lower among men with T2D.1
Laurberg told Pharmacy Times that the reason for the shift among women remains unclear. “Smoking prevalence among women in Denmark has declined substantially over recent decades. However, we do not know whether smoking patterns have changed differently among women with and without type 2 diabetes,” she said. “Such differences could potentially contribute to the observed shift, but our study did not include individual-level smoking data to investigate this. We therefore cannot determine what explains this finding.”
More broadly, the investigators cautioned that the study was designed to describe differences in incidence, not to determine whether T2D causes them. Factors such as body weight, smoking, alcohol use, and physical activity were beyond its scope, and classifying a cancer as obesity-related reflects a population-level association rather than an explanation for the differences observed.1
Implications for Pharmacist Counseling
The American Diabetes Association (ADA) 2026 Standards of Care note that diabetes is associated with increased risk of cancers of the liver, pancreas, endometrium, colon and rectum, breast, and bladder. The guidelines advise that people with diabetes be encouraged to complete age- and sex-appropriate cancer screenings and to reduce modifiable risk factors, including obesity, physical inactivity, alcohol use, and smoking.4
Screening programs for common obesity-related cancers, such as colorectal and postmenopausal breast cancer, already exist in many countries, and Laurberg’s team called for greater participation among people with T2D.1
“Pharmacists can play an important role by reminding people with T2D to participate in existing cancer screening programs, particularly for common cancers such as colorectal and breast cancer,” Laurberg said. “We know from previous research that recommendations from health care professionals can increase participation in cancer screening. Bringing up screening during relevant conversations with patients may therefore be a simple but valuable way to support participation.”
Refill and medication review visits offer natural openings for those conversations, as well as for smoking cessation support.
Questions about medication safety may also come up. The ADA states that glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have not been shown to be associated with the incidence of thyroid, pancreatic, or any other type of cancer in humans. The guidelines add that metformin and sulfonylureas may have anticancer properties but that recommendations cannot be made at this time.4
