[Epidemiology of colorectal cancer. Prospects of prevention]

Colorectal carcinoma is very common in western countries. It is in the front line of malignant pathology in France. The estimated number of new cases is almost 26,000 per year. The role played by diet in the onset of colorectal carcinomas is well established. The majority of studies indicate the protective role played by green vegetables. The role of other factors remains controversial: protective role of fibres, calcium and vitamins and favourising role of fats, proteins, red meat, alcohol and caloric intake. A number of intervention studies are underway. They should enable the proposal of a primary prevention strategy. The early detection of carcinomas and the secondary prevention of colorectal carcinoma are areas of great interest. Detection of occult blood in stools as a mass screening test is currently being evaluated. It will be necessary to wait for 1 to 4 years before being able to determine the effect on mortality and an even longer period to evaluate the effect on the incidence of colorectal carcinoma.