A colonoscopy is the best method for the diagnosis of polyps and CRC to date, and also prevents the CRC by detecting adenomatous polyps and through polypectomy. It allows the inspection of the entire lumen of the colon resulting in both distal and proximal lesions to be discovered. He has the greatest sensitivity by all methods in the detection of the CRC. The disadvantages of this method is the cost, bowel perforation and bleeding risks (especially after polypectomy), the difficulty in the preparation of patients using laxatives liquid, the need for sedation during the procedure, low levels of compliance and patient intolerance .