Pancreatic cancer is the fourth leading cause of death from cancer for men and women in the U.S. For years, pancreatic cancer and diabetes have been linked, but it still remains unclear about whether one disease causes the other.
Last year there were over 42,000 new cases of pancreatic cancer diagnosed in the U.S. The lifetime risk of getting the disease is about 1 in 76 and it is usually more common in people with diabetes, reports the American Cancer Society. The prognosis for pancreatic cancer isn't good--it's usually diagnosed at the advanced stage and only about five percent of people with the disease survive for five years.
Several studies, including one published in the New England Journal of Medicine, indicate that for people with diabetes, pancreatic cancer usually occurs within two years of diagnosis. A meta-analysis of research conducted between 1996 and 2005 found that among those newly diagnosed with diabetes the risk of the disease was nearly 50 percent compared to people who had the disease for five years or more.
Diet, weight, alcohol consumption and genetics can increase your risk of developing pancreatic cancer. So may your blood type; people with type A, B and AB appear to have a higher risk of getting the disease than people with type O blood. But will your diabetes cause the disease? The debate rages on.
What's clearer is that your diabetes treatment can make a difference. A new study in the current issue of Gastroenterology shows that the anti-diabetic medication, metformin, is associated with a 60 percent reduced risk of pancreatic cancer. Metformin is also known by the brand names Fortamet, Glucophage, Glucophage XR, Glumetza, and Riomet. In contrast, diabetics who had taken insulin or insulin secretagogues had nearly a five-fold and over a two-fold increased risks for pancreatic cancer respectively, compared with patients who never used them.
This difference remained statistically significant among patients who had diabetes for longer than two years or those who never used insulin. Other diabetes-associated factors, including history of smoking, overweight or obesity, and glycemic control, did not have a significant effect on the relationship between metformin use and pancreatic cancer risk.
"The current study demonstrated a robust protective effect of metformin against pancreatic cancer in diabetes. Our major observations were that diabetics who ever used metformin, especially those with greater than five years of use, had a reduced risk of pancreatic cancer compared to diabetics who had not taken these drugs," said Donghui Li, Ph.D., of the University of Texas M. D. Anderson Cancer Center and lead author of the study. "This adds evidence to previous study findings indicating that antidiabetic therapy can affect the development of cancer."
Sources:
Journal: The New England Journal of Medicine, Volume 331, No. 2, pp. 81-84
Date: 1994
Study: Diabetes and the Risk of Pancreatic Cancer
Website: http://content.nejm.org/cgi/content/abstract/331/2/81
Authors: Lucio Gullo, Raffaele Pezzilli, Antonio Maria Morselli-Labate, for Italian Pancreatic Cancer Study Group
Journal: Gastroenterology, Vol. 137, Issue 2, pp. 482-488
Date: August 2009
Study: Antidiabetic Therapies Affect Risk of Pancreatic Cancer
Website: http://www.gastrojournal.org/article/S0016-5085(09)00555-1/fulltext
Authors: Donghui Li, Sai-Ching J. Yeung, Manal M. Hassan, Marina Konopleva, James L. Abbruzzese
