They were age (OR, 1.04; 95% CI, 1.01–1.08), tumor location in left colon and rectum (OR, 7.31; 95% CI, 2.21-24.15), high-grade tumor differentiation (OR, 9.53; 95% CI, 3.16–28.4), T3–T4 tumor invasion (OR, 22.20; 95% CI, 1.87–262.8), and negative IHC staining results of MMR proteins, except for double-negative staining of MLH1 and PMS2 or MSH2 and MSH6 (OR, 5.09; 95% CI, 1.56–16.67) (Table 3), indicating these five variables were independent risk factors for regional LNM in dMMR/MSI colorectal cancer. The gene discussed is MLH1; the disease is colorectal cancer.