KRAS and cancer: Moreover, we found KRAS shorten the CSS in patients with cancers occurred at left colon (HR = 1.28 (95% CI [1.15–1.42]), p < 0.05) and rectum (HR = 1.23 (95% CI [1.07–1.43]), p < 0.05) but not right colon (HR = 1.07 (95% CI [0.97–1.19]), p > 0.05).