Lynch syndrome (LS), or hereditary nonpolyposis colorectal cancer (HNPCC), is a hereditary disorder predisposing for colorectal cancer. To reduce the risk of colorectal cancer, patients undergo colonoscopy every 1-2 years. Chromoendoscopy is relatively new technique which improves the detection of adenomas, the precursor lesions of colorectal cancer. The aim of this study is to determine whether chromoendoscopy, including polypectomy of all detected lesions, reduces the development of colorectal neoplasia and the need for colectomy in LS patients.