(Ivanhoe Newswire) -- A new study reveals higher insulin concentrations and insulin resistance is associated with an increased risk of pancreatic cancer in men.

Type 2 diabetes and glucose intolerance are considered risk factors for pancreatic cancer, although it has not been determined why. Researchers believe type 2 diabetes may be linked to pancreatic cancer through the growth-regulatory effects of insulin.

Experimental studies show insulin has growth-promoting effects on pancreatic cancer cells. Patients with type 2 diabetes are known to exhibit hyperinsulinemia, a condition in which insulin levels in the blood are higher than normal, during early stages of their disease. Researchers believe the condition increases their risk for pancreatic cancer.

A new study lead by Rachael Z. Stolzenberg-Solomon, Ph.D., of the National Cancer Institute, Department of Health and Human Services in Rockville, Md., examines whether fasting serum insulin and glucose concentrations are associated with risk for incident pancreatic cancer.

The study consisted of nearly 30,000 male smokers between ages 50 and 69, 400 randomly sampeled control participiants, and 169 incident pancreatic cancer cases. Researchers followed participants for nearly 17 years. They found after adjustment for age, years smoked, and body mass index, higher concentrations of glucose, insulin, and insulin resistance tended to show positive dose-response associations with pancreatic cancer.

The results support the hypothesis that higher insulin concentrations and insulin resistance may be a mechanism that explains the associations between diabetes , higher glucose concentration, and pancreatic cancer observed in previous studies.

Researchers say, although based solely on male smokers, the findings for glucose and biochemical-defined diabetes are consistent with previous studies conducted in diverse populations that have included women and nonsmokers.

Researchers hope this study will have important implications for nutrition and treatment-related cancer preventive strategies that modify or interfere with the insulin resistance pathway to help decrease the burden of pancreatic cancer.

SOURCE: The Journal of American Medical Association, 2005:294;2872-2878