PDCD1 and hepatocellular carcinoma: The current National Comprehensive Cancer Network guideline (NCCN version 1, 2025) recognizes the biological significance of PD-L1 and CTLA-4 pathways in HCC and includes immunotherapy agents targeting these checkpoints with atezolizumab (anti–PD-L1), durvalumab (anti–PD-L1), tremelimumab (anti–CTLA-4), and nivolumab plus ipilimumab (anti–PD-1/CTLA-4) as preferred or recommended options for advanced HCC [124].