MSH2 and adenocarcinoma: H&E and IHC staining indicated moderately differentiated adenocarcinomas with tubular structures of colorectal epithelial origin of colorectal epithelial origin (cytokeratin 20 (CK20)- and CDX2-positive) with wild-type p53, high proliferation rates (Ki67), and microsatellite stability (MSS; normal expression of MLH1, PMS2, MSH2, and MSH6 proteins; Supplementary Figure 1C).