The main objective of this study was to simultaneously analyze, using flow cytometry, the relative ex vivo expression of five major ICs, namely PD-1, TIGIT, Tim-3, Lag3 and NKG2A, by the CD3+ TILs of CRCs, as well as that of their ligands by the tumor cells and myeloid cells of the TME. This evidence concerns the gene KLRC1 and neoplasm.