Sequencing Systemic Therapy in Hepatocellular Carcinoma.

Multiple treatment options are now approved for unresectable hepatocellular carcinoma (HCC). An immune checkpoint inhibitor (ICI)-containing regimen should be highly considered as the first-line treatment when there is no contraindication, especially in those with hepatitis virus-related HCC, due to proven superior overall survival (OS) compared to sorafenib. Atezolizumab plus bevacizumab and durvalumab plus tremelimumab remain the treatment of choice among all ICI-containing regimens, unless contraindications to either of the medications exist. Although sorafenib is still the only medication currently approved for select patients with Child-Pugh B (CP) HCC in the first-line setting, atezolizumab plus bevacizumab is being studied in this patient population. Moreover, patients with post-liver transplantation recurrence may benefit from tyrosine kinase inhibitors (TKIs), while more studies are still needed to determine the safety of ICIs in this setting. Interestingly, multiple potential biomarkers, including tumor mutational burden (TMB), microsatellite instability (MSI) status, and PD-L1 expression level, have inconsistently predicted response to ICIs in patients with HCC. Limited evidence is available to guide treatment choice in later-line settings after progressing on ICIs, and decisions should be based on the safety profile of the treatment regimen and patient preference. Multiple trials are ongoing to elucidate the optimal treatment sequence. Of note, we believe that TKIs (e.g., cabozantinib, regorafenib, lenvatinib, and sorafenib) could be more beneficial in later-line settings to broaden inhibition of other pathways apart from vascular endothelial growth factor (VEGF). When conventional treatment options are exhausted, tissue biopsy may be helpful to reveal rare targetable mutations, such as RET gene fusions.