The route of microsatellite instability, which is a result of the malfunctioning of the DNA repair genes (DNA mismatch repair genes -MMR), leads to multiple mutations and it is the cause of 15% of sporadic type of CRC by an abnormal epigenetic methylation of the MLH1gene. Eventually, the third path, CIMP, consists of two subtypes: the first is associated with mutations in the BRAF gene, known as CIMP-High, and the second associated with mutations in the KRAS gene, known as, CIMP-Low.