It is estimated that 3–6% of colorectal cancers may be attributed to rarer familial syndromes, [13] including, but not limited to, germline mutations in MSH2, MSH6, MLH1, and PMS2 in Hereditary Non-Polyposis Colorectal Cancer (HNPCC) or Lynch syndrome, APC in Familial Adenomatous Polyposis (FAP) and STK11 in Peutz-Jeghers syndrome (PJS) [14]. This evidence concerns the gene PMS2 and Peutz-Jeghers syndrome.