Consistently, for the first time in 2006, Banville reported a case of medullary carcinoma occurring in a patient with hereditary nonpolyposis colorectal cancer (HNPCC, Lynch syndrome), with germline mutations of MSH2. This evidence once more suggests that many efforts still need to be made to better characterize the genetic alterations underlying MSI in medullary pancreatic tumor [76]. This evidence concerns the gene MSH2 and hereditary nonpolyposis colon cancer.