The immunohistochemistry analysis of MSH2 and MLH1 proteins in the index case gastric tissue has shown a positive diffuse nuclear immunostaining for MLH1 and nuclear immunostaining of MSH2 in tumor cells and normal adjacent residual glandular cells with loss of MSH2 staining in some tumor cells (incomplete immunostaining) (Figure 2B,C). This evidence concerns the gene MLH1 and neoplasm.