NCAM1 and cancer: Although CD56 is not solely specific to NK cells and is also expressed in NK-like T cells [29,30], dendritic cells, and monocytes, CD56 is considered the archetypical NK cell marker [31] and has been repeatedly used as an immunohistochemical surrogate marker for NK cells in different cancer entities including CRCs [40,41,46,87,88,89].