Lynch Syndrome II

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.

Background Lynch syndrome is caused by a pathogenic variant in one of the four Mismatch Repair genes (MMR): MLH1, MSH2/Epcam, MSH6, or PMS2. These pathogenic variants confer a higher risk of developing colorectal and other cancers, including small bowel cancer. The risk of developing a small bowel adenocarcinoma is about 100 times higher compared to individuals without Lynch syndrome, and the lifetime risk of small bowel cancer is estimated at 4,2%.
The diagnosis of a small bowel cancer depends on videocapsule endoscopy (VCE). This device is swalled so that it can record images of the small bowel, which are then stored on a wearable device for about 8 hours. The capsule is then expelled in the feces while the images are transferred to a computer to be analysed. To date, there is conflicting evidence on the efficacy of small bowel cancer screening with VCE
Rationale: this registry study will collect prospective data from patients with LS undergoing VCE
Aim: evaluate the incidence of neoplastic and pre-neoplastic lesions in patients with LS during a VCE-based small bowel cancer screening study
Design: this is a multicentric, observational study that analyzes data from diagnostic techniques already approved. Patients will not undergo diagnostic procedures beyond what would be recommended by clinical practice.