Surgery and radiofrequency ablation remain the gold standard to achieve cure in patients with hepatocellular carcinoma (HCC). After a decade in which only sorafenib was available for advanced and metastatic HCC, the emergence of other molecularly targeted drugs and immune checkpoint inhibitors (ICIs) has significantly improved the patients` prognosis. In particular, the use of ICIs has shown promising results and has revolutionized the treatment algorithm in HCC patients. Indeed, preclinical and clinical data have documented a high density of immunosuppressive cells and an increased expression of the programmed death-1 (PD-1) receptor and cytotoxic T-cell associated protein-4 (CTLA-4) in HCC. However, despite these observations, no validated biomarker is available and the molecular groundwork responsible for response to ICIs remains elusive. The anti-CTLA4 monoclonal antibody tremelimumab and the anti-PD-1 monoclonal antibodies nivolumab and pembrolizumab were the first ICIs to be tested in HCC. Recently, the combination of the anti-programmed death-ligand 1 (PD-L1) inhibitor atezolizumab and the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab demonstrated an improvement in patient outcome compared to sorafenib, becoming the standard of care in the frontline setting of advanced disease. Other immunotherapeutic agents such as pembrolizumab or the combination nivolumab-ipilimumab have shown promising results that have to be confirmed in phase III studies. Currently, the combination of different ICIs (i.e., ipilimumab, durvalumab) and anti-angiogenic agents (i.e., regorafenib, lenvatinib) is currently being tested in several trials and will hopefully revolutionize the treatment of HCC. To date, numerous studies are underway evaluating ICIs in adjuvant and neoadjuvant settings to improve survival in early and intermediate stages. Thus, this review focuses on the rationale for ICIs and their potential use for early or intermediate HCC stages.

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver and the third leading cause of cancer-related death worldwide. Liver transplantation (LT) is the best therapy for most patients with non-metastatic HCC. In recent years, the management of patients with HCC has changed considerably, thanks to the improvement of molecular biology knowledge and the introduction of immunotherapy. To date, systemic therapy is authorized in the Western world only in patients with advanced HCC. However, this therapy could lead not only to stabilize the tumour disease or improve survival but could display excellent response and lead to downstaging of the tumor that finally permits liver transplantation. There are increasing reports of patients that have performed liver transplantation after pretreatment with immune checkpoint inhibitors (ICIs). However, due to the intrinsic mechanism of ICIs to stimulate the immune response against tumors, they could also cause graft rejection. This review aims to evaluate the readiness and outcomes of liver transplantation in patients with advanced HCC who have previously undergone treatment with ICIs. It seeks to identify the challenges, risks, and benefits associated with this conversion therapy. The integration of ICIs into the treatment paradigm for advanced HCC necessitates a nuanced approach to liver transplantation. While early evidence supports the feasibility of LT following ICI therapy, there is an urgent need for standardized guidelines and more extensive longitudinal studies to optimize patient selection, timing, and post-transplant management.