Cancer of the pancreas is slightly more common among men than women. Survival rarely exceeds six months. Trends in pancreatic cancer incidence in developed countries are slightly declining. The disease shows evidence of a familial occurrence. Tobacco smoking is the only established exogenous cause of the disease; smoking cessation is quickly followed by a reduction in risk. Consumption of fruits and vegetables is inversely associated. Alcohol, either consumed in moderate amounts or abused, does not substantially affect risk, although pancreatitis, frequently linked to excessive alcohol intake, has been found to slightly increase the risk of the disease. Among occupational factors the evidence is relatively strong only for chlorinated hydrocarbon solvents frequently used in dry cleaning. Adult-onset diabetes mellitus and perhaps pernicious anemia may increase the risk of pancreatic cancer, possibly through the action of gastrointestinal hormones or insulin. Several reports indicate that allergies may be inversely related to the risk of pancreatic cancer.