PDCD1 and hepatocellular carcinoma: Our results are supported by Sun et al.’s study of 235 patients with HCC treated with programmed cell death-1 blockade therapy, where ≥ 50% reductions in both PIVKA-II and AFP levels significantly correlated with longer PFS (p<0.001 and p=0.021, respectively) and OS (p=0.003 and p=0.006, respectively) (33).