KRAS and adenoma: At the biological level, colon carcinogenesis typically follows the classical adenoma–carcinoma sequence, in which stepwise accumulation of genetic and epigenetic alterations in adenomatous polyposis coli (APC), Kirsten rat sarcoma viral oncogene homolog (KRAS), tumor protein p53 (TP53) and related pathways drives progression from benign adenoma to invasive carcinoma [7].