Researchers at New York University's School of Medicine found that diabetes increased the risk of cancer death among Asians by an average of 26 percent, a statistic similar in the West.
Data for the new study drew on an analysis of 770,000 people with Type 2 diabetes throughout East and South Asia. Diabetics were followed for an average of 13 years to see if they developed cancer and what types. During that time more than 37,300 cancer deaths were identified.
Yu Chen, an epidemiology professor at the NYU School of Medicine’s Department of Population Health who was the study's lead author, says Asians with Type 2 diabetes are more likely to be diagnosed with rarer cancers than Westerners, including cancers of the liver, thyroid and kidney which was double the risk compared to non-diabetics in Asia.
There was also a more than two and a half times increased risk of cancer of the endometrium and a 1.7 times higher risk of breast cancer among diabetic Asians compared to those who were not diabetic.
The number of cancers of the gallbladder and bile ducts in Asia were comparable to those in the West, according to Chen. Those sites are closer in the body to the pancreas, where insulin is made.
Chen thinks there may be several mechanisms at work, but data suggests that insulin may in some way stimulate the growth of cancer.
“Patients with diabetes that have high levels of insulin, some cancers are very sensitive to insulin, so it may promote the tumor growing,” she said.
The findings were published in the journal Diabetologia.
Chen said the study was undertaken because there's been little research on an association between diabetes and cancer in Asia.
She said the research suggests Type 2 diabetes should be added to the list of cancer risk factors, along with diet and cigarette smoking.
“Cancer prevention needs to take into account for diabetes the lifestyles related to diabetes – [which] may reduce the risk of diabetes and also cancer,” she said.
Chen suggested that diabetics should receive more cancer screenings, in addition to medical interventions to reduce the risk of diabetes overall.