LAS VEGAS — Genetic variations in two major antioxidant enzymes may increase the risk of pancreatic cancer in people with diabetes mellitus, according to a study presented at the annual meeting of the North American Association for the Study of Obesity.
An ongoing, hospital-based, case-control study found that 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; the majority had type 2 diabetes.
“Any change in these genotypes would make the individual at high risk of pancreatic cancer,” said Manal M. Hassan, M.D., a molecular epidemiologist at the University of Texas M.D. Anderson Cancer Center, Houston, in her report of the preliminary finding in a late-breaking poster added to the program.
Type 2 diabetes is a significant risk factor for pancreatic cancer. Dr. Hassan said the investigators hypothesized that an impaired defense against oxidative stress makes some patients more susceptible to pancreatic cancer.
The study has so far compared 556 cases of pathologically confirmed 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 patients, she said.
The researchers hope to develop a model that could identify which patients are most susceptible. “A large-scale study, to assess the interaction between our findings and obesity indicators such as weight change, is warranted,” Dr. Hassan said.