Finally, dMMR was associated with shorter OS only in the left colon (p = 0.010 for interaction), as shown in Fig. 3, while mutated KRAS was associated with shorter DFS in the subset of patients with left colon tumors (HR = 2.30, 95 %CI 1.17–4.52, p = 0.020), but not in those with stage II disease. This evidence concerns the gene KRAS and colonic neoplasm.