LAS VEGAS — Genetic variations in two major antioxidant enzymes may increase the risk of pancreatic cancer in people with diabetes mellitus, according to preliminary data presented at the annual meeting of the North American Association for the Study of Obesity.
In an ongoing, hospital-based, case-control study, pancreatic cancer risk was nearly four times higher (odds ratio, 3.8) in diabetic patients who had a catalase variant. The risk was nearly six times higher (odds ratio, 5.7) if they had a variant of superoxide dismutase. The patient population included both type 1 and type 2 diabetics; most had type 2 diabetes, said Manal M. Hassan, M.D., a molecular epidemiologist at the University of Texas M.D. Anderson Cancer Center, Houston.
Type 2 diabetes is a significant risk factor for pancreatic cancer. The researchers hypothesized that an impaired defense against oxidative stress makes some patients more susceptible to pancreatic cancer.
The study has so far compared 556 confirmed cases of adenocarcinoma of the pancreas with 344 spouses of M.D. Anderson patients who had other forms of cancer. The goal is to enroll 800 pancreatic cancer cases, Dr. Hassan said.
The researchers hope to develop a model to identify patients who are most susceptible. “A large-scale study, to assess the interaction between our findings and obesity indicators such as weight change, is warranted,” the researchers concluded at the meeting, which was cosponsored by the American Diabetes Association.