Abstract
Since the introduction in the Federal Republic of Germany of free routine screening for colorectal carcinoma (digital examination of the rectum in 1971; test for occult blood in the faeces in 1977), the number of Dukes' stage A cases diagnosed at one hospital has increased by 30%. The average interval between onset of symptoms and diagnosis has shortened from 5 to 3.8 months, and the proportion of inoperable carcinomas has decreased by 10%.