Diabetes May Raise Cancer Risk
Study Shows Liver, Kidney, and Pancreatic Cancers More Frequent in Diabetes Patients
Sept. 25, 2006 -- Adults with diabetes may be at increased risk for developing several kinds of cancer, according to new research from Japan.
In the study, men with diabetes were found to have more liver, kidney, and pancreatic cancers than men without the disease. And women with diabetes had more stomach and liver cancers than women who didn't have diabetes.
The Japanese study presents some of the strongest evidence yet linking diabetes and cancer, but it is not yet clear if diabetes actually causes malignant disease, researchers from the National Cancer Center, Tokyo, wrote.
Diabetes Rates on the Rise
As with other industrialized countries, including the U.S., diabetes rates have skyrocketed in Japan in recent years, and they continue to rise.
Approximately 150 million people worldwide have diabetes. But that number is expected to double within the next two decades as the population ages.
"The remarkable increase in the diagnosis of diabetes in Japan in recent years may affect future trends in the incidence and type of cancer," the Japanese researchers write in the Sept. 25 issue of the Archives of Internal Medicine.
Researcher Manami Inoue, MD, PhD, and colleagues followed nearly 98,000 men and women in Japan for 9 to 13 years. Participants were between the ages of 40 and 69 when they entered the study.
At enrollment, 3,097 of the men (6.7%) and 1,571 of the women (3.1%) had diabetes or had a history of having the disease. By the end of the study's follow-up in December 2003, 3,907 men, including 366 with diabetes, and 2,555 women, including 104 with diabetes, had developed cancer.
Total cancer risk was found to be 27% higher for men with diabetes than for men without the disease. For women with diabetes, they found an increased risk for stomach and liver cancers specifically.
Among men, the risk was especially high for cancers of the liver, kidney, and pancreas.
The Role of Obesity
Obesity is one of the biggest risk factors for type 2 diabetes; it is also a well-established risk factor for certain cancers, including those of the colon, endometrium (inner lining of the uterus), breast, kidney, and esophagus.