To identify patients with Lynch syndrome and triage them for germline mutational analysis, MMR-IHC (plus MLH1 promoter methylation status analysis in the case of immunohistochemical loss of MLH1/PMS2 expression) or MSI testing should be performed in all endometrial carcinomas, regardless of the histological subtype of the tumor (III, B). This evidence concerns the gene MRC1 and endometrial carcinoma.