Background: Small bowel adenocarcinoma (SBA) is a rare disease which can be associated with Lynch syndrome (LS). LS tumors are characterized by the presence of microsatellite instability (MSI) and/or the loss of mismatch repair (MMR) protein expression. In SBA, the frequency of MMR deficient (MMRd) tumors varies from 5% to 35%. This study aims to describe the prevalence of LS carriers among patients with MMRd small bowel adenocarcinomas. Methods: A multicenter retrospective study with identification and MMR testing of all consecutive SBA between 2004 and 2020 in a multicenter Spanish study. Demographical data, tumor characteristics, follow-up and survival information were collected. Germline testing was driven by identification of MMRd tumors. Results: A total of 94 individuals diagnosed with SBA were recruited. We observed 20 (21.3%) MMRd tumors. In 9/15 (60%) patients with MMRd tumors, a pathogenic variant was identified (three MLH1, four MSH2, one MSH6 and one PMS2). Accordingly, the prevalence of LS among all SBA cases was 10.1%. Conclusions: More than one-fifth of SBA display MMRd and in more than a half is due to LS. Our data supports the implementation of universal MMR tumor testing among SBA for the identification of LS families.
Lynch syndrome; Hereditary cancer; Small bowel adenocarcinoma
Sánchez A, Bujanda L, Cuatrecasas M, Bofill A, Alvarez-Urturi C, Hernandez G, et al. Identification of Lynch Syndrome Carriers among Patients with Small Bowel Adenocarcinoma. Cancers. 2021 Dec 20;13(24):6378.
Use this identifier for quote and/or link this documenthttp://hdl.handle.net/11351/7629
This item appears in following collections
The following license files are associated with this item: