In the present study, through in-depth cytofluorimetric analysis of the expression of different ICs that critically regulate NK cell function, we observed a significant enrichment of tumor-associated NK cells expressing certain ICs (i.e., KIR, NKG2A, and TIM-3) compared to NK cells from tumor-free tissue, along with an increase in PD-1+ NK cells in tumor tissue, compared to both PB and tumor-free tissue. This evidence concerns the gene KLRC1 and neoplasm.