[Screening and prevention of carcinoma of the colon and rectum].

Carcinoma of the colon and rectum is the third most frequent malignant disease in industrialised countries. Incidence and mortality of colon cancer can be effectively lowered by population screening. The individual risk status of the patient has to be assessed before the screening procedure. In people with an average risk screening should be performed after the 50th birthday. The choice of the applied procedure (endoscopic procedures or fecal occult blood test) depends on the individual situation of the patient. Complete colonoscopy has the highest sensitivity and specificity for the detection of adenomas or carcinomas and should therefore be offered first. Alternatively flexible sigmoidoscopy or repetitive testing for occult blood can be applied. Despite promising developments in the radiographic detection of colonic lesions, virtual colonoscopy cannot be recommended as a screening procedure.