Souria Aissaoui
Aix-Marseille University, France
Title: Genetic mutation risk calculation in Lynch syndrome inheritance: Evaluating the utility of the PREMM1,2,6 Model in a French population.
Biography
Biography: Souria Aissaoui
Abstract
Lynch syndrome is due to germline mutations in mismatch repair genes: MLH1, MSH2, MSH6 and PMS2. It is characterized by an increased risk of various cancers including colorectal and endometrial cancers. Early diagnosis of these patients allows appropriate surveillance that improves survival rate. Differentiating between patients who should undergo genetic testing and those for whom it is not necessary is difficult despite various established criteria (Amsterdam and Bethesda). Often, health professionals meet in Multidisciplinary Committees (MDC) to discuss patients cases regarding Lynch syndrome. In this study, we wanted to know if the prediction model PREMM1,2,6 could be used to enhance MDC decision-making and whether it could be included in our own routine practice and in those of other French teams. In our cohort, using the prediction model would have avoided 12% of analyzes decided by the MDC, and would have detected all patients with a mutation in MMR genes. In addition, the study suggested that the decision-making criteria used by the professionals in our MDC was too restrictive since we should have performed 20% more genetic testing according to the model. These results suggest that PREMM1,2,6 should really be used in current practice to validate the decisions of the MDC before genetic testing in complex cases. It should also be coupled with immunohistochemistry as major quality criteria for genetic testing as previously reported in the literature.