CRC risk may be highest among men with Type 2 diabetes, study finds

NEW YORK There may be a link between Type 2 diabetes and colorectal cancer among men, according to a new study published in Gastroenterology.

In a final study of 73,312 men and 81,663 women — which were participants selected from the prospective study "Cancer Prevention Study II Nutrition Cohort" — 1,567 men (227 with Type 2 diabetes) and 1,242 women (108 with Type 2 diabetes) were diagnosed with colon or rectal cancer by 2007. Among men, Type 2 diabetes was associated with increased risk of incident CRC compared with not having Type 2 diabetes. CRC risk was higher for those participants with Type 2 diabetes regardless of whether or not they used insulin.

Among women, Type 2 diabetes and insulin use were not associated with CRC risk, the authors said, which may support recent observations that the association may be more prominent in men than in women, and raise the possibility of a stronger association among individuals with a family history of CRC. The authors speculated that the lack of an association between Type 2 diabetes and CRC risk among women might relate to improved glucose control among women with Type 2 diabetes in recent years.

"While our study supports an association of Type 2 diabetes with colorectal cancer incidence among men, our results also suggested that insulin use is associated with a slight, but not a substantially increased, risk of colorectal cancer among men with Type 2 diabetes," said Peter Campbell of the American Cancer Society and lead author of this study. "Prevention strategies should emphasize adherence to guidelines intended for the general population, such as smoking cessation, weight management, exercise and regular early detection exams."