Emerging Role of Immune Checkpoint Inhibitors in Hepatocellular Carcinoma

Hepatocellular carcinoma is the most common primary liver cancer and the fourth leading cause of cancer death worldwide. A total of 70-80% of patients are diagnosed at an advanced stage with a dismal prognosis. Sorafenib has been the standard of care for almost a decade until 2018 when FDA approved an alternative first-line agent namely lenvatinib. Whereas FOLFOX4 results an alternative first-line treatment for the chinese clinical oncology guidelines. In addition to cabozantinib, regorafenib, and ramucirumab, two therapeutics against the PD-L1/PD1 axis have been recently approved for subsequent-line therapy, as nivolumab and pembrolizumab. However, similar to other solid tumors, the response rate of single-agent targeting PD-L1/PD1 axis is low. Therefore a lot of combinatory approaches are under investigation, including the combination of different immune checkpoint inhibitors, the addition of immune checkpoint inhibitors after resection or during locoregional therapy, immune checkpoint inhibitors in addition to kinase inhibitors, anti-angiogenic therapeutics, and others. This review focuses on the use of ICIs for the hepatocellular carcinoma with an attent evaluation of new ICIs based combinatory approaches.