For example, the combination of ipilimumab (an anti-CTL-associated antigen 4 antibody) and nivolumab (an anti-PD-1 antibody) is approved with a 32% response rate in second-line HCC treatment45, which is similar to what was observed in the present study; however, more than half of the patients experienced serious irAEs. This evidence concerns the gene PDCD1 and hepatocellular carcinoma.