The findings from a study of ethnic Chinese subjects residing in Singapore support what has been shown in Western populations; diabetes is associated with an increased risk of colorectal cancer.

Dr. Adeline Seow, from the National University of Singapore, and colleagues evaluated the link between diabetes and colorectal cancer in Singapore, in part because the body type and lifestyle of residents are different from people living in Western countries. For instance, people from Eastern countries tend to be leaner than their peers in Western countries.

The new study, which appear in the Journal of the National Cancer Institute, involved more than 60,000 subjects who provided detailed dietary, medical, and lifestyle information and then were followed for several years to assess the occurrence of colorectal cancer and related risk factors.

A total of 636 cases of colorectal cancer occurred during follow-up, the report indicates.

A subset of men and women with a history of diabetes were 50 and 40 percent, respectively, more likely to develop colorectal cancer than their peers without diabetes. On further analysis, a significant association was still noted among diabetic patients with high total calorie intake and low physical activity levels.

“Our results support the hypothesis that (high insulin levels) may play a role in the (development of colon cancer), even in a relatively lean population,” the investigators conclude.

SOURCE: Journal of the National Cancer Institute, January 18, 2006.