Lynch Syndrome X-Talk of Enteral Mucosa With Immune System

Lynch syndrome (OMIM #120435) is the most common dominantly inherited colorectal cancer syndrome with an estimated prevalence of 1:270 individuals. It increases the lifetime risk of colorectal and endometrial cancer primarily, but it is associated with a high risk of other cancers (pancreas, stomach, ovarian, central nervous system, skin, among others). It is caused by a germline mutation in one of four DNA mismatch repair genes or a terminal deletion of the MSH2-adjacent gene EpCAM. Despite adherence to cancer surveillance programs, many patients still develop colorectal cancer and endometrial cancer. The Prospective Lynch Syndrome Database (PLSD) suggests that more frequent surveillance intervals do not significantly improve cancer risk reduction. The PLSD also revealed that the incidence of colorectal cancer in MLH1 and MSH2 carriers was even higher than previously expected, reaching as high as 41-36% among MLH1 carriers, regardless of ethnic background. The development of colorectal cancer despite surveillance is an unresolved question. Therefore, there is an unmet need for effective cancer prevention strategies.