[Individual screening for colorectal cancer: which strategy for which patient?]

Currently, more than 4,000 newly colorectal cancer are diagnosed each year in Belgium. The individual average-risk for developing colorectal cancer is about 5%. 90% of colorectal cancer occurred after the age of 50, and in 70% of the cases in patients without particular risk factors (average-risk population). Personal and/or familial history of colorectal adenoma, colorectal cancer, inflammatory bowel disease localised to the colon, familial polyposis syndrome or Hereditary Non Polyposis Colorectal Cancer (HNPCC) increase the risk of colorectal cancer. An individual appropriate screening of high-risk patients and average-risk asymptomatic patients older than 50, together with endoscopic resection of adenoma decrease the incidence and the mortality of colorectal cancer. Usual screening methods are fecal occult blood testing which is not proven to be efficient alone for individual screening (but still recommended for general population's screening), sigmoidoscopy (which has to be completed by a colonoscopy, if lesions founded), and colonoscopy. Virtual colonoscopy and genetic testing need further evaluation. Currently, colonoscopy seems to be the goldstandard method providing complete examination of the whole colon and being the most cost-effective method. Screening strategy should be decided on an individual basis considering the patient's benefit with respect to the informed consent.