This is an observational, case-control study evaluating the quantitative level of Septin9 in plasma pre- and post-colectomy in hereditary colorectal cancer (CRC) syndrome patients (Familial Adenomatous Polyposis (FAP), Lynch syndrome (also known as HNPCC), and Multiple Adenomatous Polyposis (MAP, also known as MYK/MYH) cases) and genetically related FAP-family members as controls and references.