Hepatocellular Carcinoma: The Role of Immunotherapy and Transplantation in the Era of Transplant Oncology

SIMPLE SUMMARY: Hepatocellular carcinoma (HCC) is a common cause of cancer-related deaths worldwide. During the early stages of the disease, HCC can be treated with surgery or radiofrequency procedures. Most HCC cases are discovered at later stages when these therapies cannot be used, and a treatment such as a liver transplant is needed. Recently, new options for the treatment of advanced HCC are available, called immune checkpoint inhibitors (ICIs). ICIs have been found to be safe and effective. However, there is concern that liver transplant patients may face graft rejection in both the pre- and post-transplant settings. Our review found that ICIs may be useful, especially in the pretransplantation setting. More data are needed to carefully select patients who will benefit from ICI treatment in both settings so that they can benefit from it while reducing harm. ABSTRACT: Hepatocellular carcinoma (HCC) is one of the most common causes of cancer deaths worldwide. As most patients present with advanced disease, curative therapy such as surgical resection and radiofrequency ablation are rarely utilized. With the advent of immunotherapy, historical treatment approaches such as liver transplantation are being challenged. In particular, the use of immune checkpoint inhibitors (ICIs) has emerged as a safe and useful option in the treatment of HCC. However, there is concern over adverse effects, such as graft rejection and graft loss. This updated review discusses the role of immunotherapy in the pre- and post-transplantation setting and provides insights into the potential of immunotherapy as an adjunct to liver transplantation. We deliberate on the use of ICI in the setting of the Milan criteria as well as the University of California San Francisco’s expanded criteria for liver transplantation. Current data suggest that ICI has utility, especially in the pretransplantation setting. Nevertheless, larger, purposefully designed clinical trials are needed to clearly identify patients who will benefit most from ICI treatment in the transplant setting and determine parameters that will minimize the risk of graft rejection and maximize the benefits of this adjunct treatment.