[Descriptive epidemiology of cancer of the pancreas]

Cancer of the pancreas is a relatively common malignancy in France, where it represents 10% of all digestive tract cancers. Over the world, there is little variation in incidence rates; Europe, North America, South America, Oceania and parts of Asia represent high risk areas. The regions with the lowest incidence rates are India, mid-western countries and Africa. In most countries, pancreatic cancer incidence rates increased between 1950 and 1965; however little change in incidence has been observed over the past 20 years. Pancreatic cancer occurs more frequently in males than in females in all age groups. No consistent differences have been identified in urban/rural distribution or in socioeconomic status. Studies of migrant populations and some religious groups indicate that environmental factors are of overwhelming importance in determining the incidence of pancreatic cancer in a given population. In the same areas, difference in incidence has been reported among various ethnic groups: in the United States the rate is higher in Blacks than in Whites, in New Zealand in Maoris and Polynesians than in Whites, in Israel in Jews than in non-Jews. This data leads us to the conclusion that diet is of importance in pancreatic cancer etiology. No premalignant lesion has been clearly identified. Particular attention has been paid to diabetes mellitus and chronic pancreatitis, but a firm conclusion cannot be drawn. Some potentially valuable clues for clarifying the etiology of pancreatic cancer have been found by way of descriptive epidemiology. In view of the severe prognosis of the disease, there is an urgent need for further aetiological studies in order to develop effective methods of prevention.