Interestingly, when stage II colon and rectal tumours were analysed separately, only the presence of a KRAS mutation in colon cancers was associated with a trend towards a worse DFS (HR, 3.64; P=0.07), and these results were maintained in the Cox regression analysis (HR, 4.163; P=0.07). Here, KRAS is linked to malignant colon neoplasm.