Obese women who carry most of their extra weight around the stomach are 70 percent more likely to develop pancreatic cancer, an international team of researchers reported.
The findings suggest are some of the first evidence that the link between obesity and pancreatic cancer is as strong in women as in men, Juhua Luo of Sweden's Karolinska Institute and colleagues reported in the British Journal of Cancer.
"We found that the risk of developing pancreatic cancer was significantly raised in obese postmenopausal women who carry most of their excess weight around the stomach," she said in a statement.
"Obesity is a growing and largely preventable problem, so it's important that women are aware of this major increase in risk."
Pancreatic cancer is the fifth leading cause of cancer death worldwide. It accounts for only about 2 percent of the cancers diagnosed each year but the first-year survival rate is less than 5 percent, according to Johns Hopkins University in Baltimore.
Stronger link for obese men, too
Until now, smoking and chronic pancreatitis were the most well-established risk factors for the disease in men and women, with much of the evidence also pointing to a stronger obesity link for men.
As part of a large study known as the Women's Health Initiative, Luo and colleagues followed more than 138,000 menopausal women in the United States for more than seven years to investigate the links between obesity and pancreatic cancer.
They found that 251 women developed the disease, and of these, 78 had the highest waist-to-hip ratios. After factoring in other risk factors, this was 70 percent more than the 34 women with the lowest excess stomach weight who got pancreatic cancer.
The findings also suggest that excess weight around the stomach may better predict the disease than the traditional Body Mass Index, or BMI, measurement for obesity, the researchers said.
They also suggested that obesity could increase the risk of pancreatic cancer by affecting insulin levels, and that diabetes may also play a role. Obesity is one of the main risk factors for diabetes.
"We know that carrying a high proportion of abdominal fat is associated with increased levels of insulin, so we think this may cause the link between obesity and pancreatic cancer," the researchers said.
Several studies have shown that obesity raises the risk of several types of cancer including breast and colon as well as heart disease and other conditions.