CEACAM5 and colorectal carcinoma: The discovery of the carcinoembryonic antigen (CEA) as a tumor marker for colorectal carcinoma in 1965 by Gold and Freedman [1] was the milestone for identifying a much wider family of 12 carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) which mediate intricate mechanisms of modulation and dysregulation during complex biological processes regarding cancer progression, inflammation, metastasis, and angiogenesis [2].