MRC1 and endometrioid adenocarcinoma: The baseline clinical and pathologic characteristics of the study population are represented in Table 1, and the IHC for the MMR proteins are illustrated in Figure 1A. In the IHC analysis and MLH1 methylation test for the primary endometrioid carcinoma from 173 patients, loss of MMR IHC was observed in 45 cases (26.0%).