Medical Research: What is the background for this study?
Dr. Vasen: People with familial colorectal cancer (CRC) have a 3-6 fold increased risk of colorectal cancer. It has been estimated that about 2% of the population have familial CRC (about 2.7 million people in the US). Previous studies showed that colonoscopic surveillance reduces the CRC-mortality by >80%. In people with hereditary CRC, i.e., Lynch syndrome (10 fold increased risk of CRC), an intensive screening program with colonoscopy 1x/1-2 years, is recommended. In familial colorectal cancer, the optimal screening program is unknown.