Recent Advance of Local Ablation for Hepatocellular Carcinoma

Local ablation has been accepted in many treatment guidelines as a good alternative to curative resection or transplantation for patients with unresectable hepatocellular carcinoma (HCC). The main advantage of local ablative therapy is minimal invasiveness, guaranteeing low morbidity even for the patient with poor hepatic reserve. Furthermore, the therapeutic efficacy of local ablation, especially radiofrequency ablation (RFA), has been shown to be as effective as surgical resection for early-stage (smaller than 3 cm, less than 4 in number) HCC. The long-term outcome after radiofrequency ablation for HOC reported in large series studies were overall survival of 50% to 60% at 5 years and 27 to 32% at 10 years. Major complication rates are 0% to 2.4%. However, controversy remains regarding whether local ablation can replace surgical resection because many retrospective comparative studies have produced conflicting results. Only a well-designed randomized study will be able to clearly answer this long-standing question. During the past decade, many technical advancements in local ablation have been reported, including novel electrodes, thermal protection (i.e., artificial ascites), fusion image guidance, Sonazoid-enhanced ultrasound guidance, and emerging energy sources (i.e., microwaves, High internsity focused ultrasound, Irreversible electroporation). Local ablation is still an evolving technique in the era of minimally invasive treatment for HOC. Many more technical advances are ongoing to enhance the therapeutic efficacy of local ablation. In summary, local ablation will remain a mainstay of non-surgical treatment early stage HOC and play an important role in multidisciplinary approach for HCC management.