The treatment involving ICIs, particularly targeting cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), programmed death-1 (PD-1), programmed death ligand-1 (PD-L1), and lymphocyte activation gene-3 (LAG-3), has been proven effective in activating anti-tumor T-cell activity and dynamically regulating the anti-tumor immune response (6). Here, PDCD1 is linked to neoplasm.