Clinical trials have shown that blocking cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) or programmed cell death-1 (PD-1)/programmed death ligand 1 (PD-L1) is active, tolerable, and clinically beneficial against advanced HCC, but the highest response rate is approximately 20%. This evidence concerns the gene PDCD1 and hepatocellular carcinoma.