Bridging to liver transplantation in HCC patients

Liver transplantation (LT) is the only cure for patients diagnosed with unresectable hepatocellular carcinoma (HCC), and HCC has become the leading indication for LT in the USA. The shortage of liver grafts results in a significant waiting time for LT with the risk of tumour progression. Treating HCCs during the waiting time prior to transplantation (bridging therapy) is an attractive strategy to reduce the risk of exceeding the tumour criteria for transplantation. Studies on bridging therapy are heterogenous and due to ethical issues, mostly of retrospective design.

We summarize the main studies and methods that have been reported on bridging therapies for patients with HCC waiting for a LT.

During the waiting period for LT, patients with HCC at risk for tumour progression and therefore bridging therapy is recommended for patients with an estimated waiting time of ≥6 months. Bridging therapy for patients with HCC prior to LT mainly include locoregional therapies (LRTs), with transarterial chemoembolization (TACE) being the most common, followed by radio frequency ablation (RFA). Because of a continuous enhancement of therapy options, including a more precise adjustment of external radiotherapy, further possibilities for an individualized bridging therapy for patients with HCC have been developed. Patients with compensated liver cirrhosis and small tumour size are preferably treated with RFA, whereas patients with larger tumour size but compensated liver function are treated with TACE/TARE. Patients with uncompensated liver cirrhosis and larger tumour size can nowadays be successfully bridged to LT with external radiotherapy without increasing the risk for further deterioration of liver function.