CEACAM5 and colorectal carcinoma: Oncogenetic molecular variables including DNA ploidy, expression of oncogene and anti-oncogene (mutation of Ki‐ras oncogene, mutation of Deleted in Colorectal Carcinoma/DCC, p53, nm23 gene and other allele aberrations), tumor-related antigen and other immunological factors (carcinoembryonic antigen/CEA, Mucin-associated antigen, Human leucocyte antigen DR/HLA-DR and The epidermal growth factor receptor/EGFR) are thought to play important roles at different stages of colorectal carcinogenesis [[14], [15], [16]].