Epidemiology of pancreatic cancer: an update.

Pancreatic cancer, although infrequent, has a very poor prognosis, making it one of the 4 or 5 most common causes of cancer mortality in developed countries. Its incidence varies greatly across regions, which suggests that lifestyle factors such as diet, and environmental factors, such as vitamin D exposure, play a role. Because pancreatic cancer is strongly age-dependent, increasing population longevity and ageing will lead to an increase of the global burden of pancreatic cancer in the coming decades. Smoking is the most common known risk factor, causing 20-25% of all pancreatic tumors. Although a common cause of pancreatitis, heavy alcohol intake is associated only with a modest increased risk of pancreatic cancer. While viruses do not represent a major risk factor, people infected with Helicobacter pylori appeared to be at high risk of pancreatic cancer. Many factors associated with the metabolic syndrome, including overweight and obesity, impaired glucose tolerance, and long-standing diabetes also increase the risk disease, while atopic allergy and use of metformin as a treatment for diabetes have been associated with a reduced risk of pancreatic cancer. A family history of pancreatic cancer is associated with an increased risk of pancreatic cancer and it is estimated that 5-10% of patients with pancreatic cancer have an underlying germline disorder. Having a non-O blood group, another inherited characteristic, has also been steadily associated with an increased risk of pancreatic cancer. While many risk factors for pancreatic cancer are not modifiable, adopting a healthy lifestyle could substantially reduce pancreatic cancer risk.