[Epidemiology of colorectal carcinoma in Cantabria].

Colorectal cancer is increasing due to both a real increase and a better diagnosis. More cases are seen in men than in women (ratio 1.45). The incidence increases with age, reaching the highest point at 75 years of age in men and at 84 years of age in women. Before 50 years of age, the risk of colorectal cancer is higher in women; the contrary happens after this age. Colorectal cancer is localized in the rectum (47.5%), sigmoid flexure (25.3%) and coecum (8.1%). Synchronous colorectal carcinomas are seen in 2.3% of the patients, frequently coexisting with multiple adenomas, and show a tendency to be localized out of the rectum. A higher proportion of carcinomas localized in the descending colon and a diminution of rectum carcinomas are observed in men with increasing age, while in women the number of carcinomas of the ascending colon increases and that of the descending colon decreases. For the considered period (1970-81), a diminution of the ascending colon carcinomas has been registered.