Thermal ablation for hepatocellular carcinoma: what's new in 2019

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide, but a major proportion of patients are not appropriate candidates for surgical resection or transplantation. For this reason, image-guided tumor ablation using thermal energy for early-stage HCC has become an accepted curative treatment option in all HCC treatment guidelines due to its minimal invasiveness and proven outcomes. In recent years, microwave ablation (MWA) has been gaining popularity worldwide over radiofrequency ablation (RFA) due to its better performance with high temperature heating and lack of heat sink effects. However, more high-level evidence of real survival gain is required before MWA will completely replace RFA. Although cryoablation and irreversible electroporation are promising for safe and effective ablation in the liver, clinical evidence for these remains limited. In addition to specific ablative modalities, therapeutic outcomes can be improved by current technological advances in fusion imaging, contrastenhanced ultrasound, and post-ablation antiviral therapy. In fact, immuno-ablation has the great potential to maximize therapeutic outcomes after ablation. The purpose of this review is to briefly illustrate the current status of ablation in HCC treatment guidelines and update on recently introduced therapeutic outcomes and new advances in ablation-related techniques.