Study: Diabetes May Up Cancer Risk

Japanese adults with diabetes may have a higher risk of cancer overall and in several organs, including the liver, pancreas and kidney, a study finds.

Dr. Manami Inoue of the National Cancer Center in Tokyo studied the association in 97,771 Japanese males and females ages 40 to 69 who were enrolled in the study between 1990 and 1994.

The participants completed a lifestyle questionnaire on smoking, alcohol drinking, medical history, physical activity and food and beverage intake. They were also asked if they had ever been diagnosed with diabetes or taken diabetes medications.

Men with diabetes had a 27-percent higher risk of developing cancer than men without diabetes; the risk was especially high for liver, kidney and pancreatic cancer. Among women, those with diabetes had a 21-percent higher risk of cancer than those without — although this increased risk was not statistically significant. However, there was a significantly higher risk for stomach and liver cancer and a borderline higher risk for ovarian cancer, according to the study published in Archives of Internal Medicine.

It is unclear exactly how diabetes might contribute to cancer, but the researchers suspect that excess insulin in diabetic patients may promote growth in the cells of these organs, increasing cancer risk.