KRAS and colorectal cancer: The analysis of mutated genes in MSS colorectal cancers showed the occurrence of 47 recurrently mutated genes, the most frequently mutated being APC (79%), TP53 (78%), KRAS (44%), PIK3CA (18%), SMAD4 (16%), TCF7L2 (10%) and FBXW7 (10%) (Figure 7) [201].