CEACAM5 and colorectal carcinoma: Although many tumor-associated antigens (TAA) have been already found in CRC cells, such as CEA (carcinoembryonic antigen)13,14, WT1 (Wilms’ tumor gene 1)15,16, MUC1 (mucin 1)13, MAGE (melanoma-associated antigen gene)17–19, p5320, the heterogeneity and patient-specificity are severe obstacles to use the anti-TAA therapies.