Recent advances in radiofrequency ablation in the treatment of hepatocellular carcinoma and metastatic liver cancers.

Hepatocellular carcinoma (HCC) and liver metastases are common cancers worldwide. Recent imaging modalities have been able to detect HCC and liver metastases at an early stage, with surgical resection as the choice of management. However, because of poor liver reserve, co-existing liver cirrhosis and multiplicity of tumors, resection is only feasible in 10-30% of HCC or liver metastases on presentation. Thus, various local tumor ablation modalities are being developed to effectively ablate small liver tumors. Of these, percutaneous ethanol injection and radiofrequency (RF) ablation (RFA) are the two best options because of their high effectiveness and minimal invasiveness. RFA has the particular advantage of more predictable ablation areas and fewer treatment sessions required. It has been applied for local ablation of liver malignancy since 1990 and is currently widely accepted as an alternative to resection in small, un-resectable or even resectable liver malignancies. Because current RF devices can only effectively ablate 3 cm tumors in a single RF electrode introduction, recent advances have focused exclusively on improving RF devices, including the design of electrodes and the algorithm to magnify the ablation zone in a single session or over a short duration. This review article updates results of RFA for HCC and liver metastasis in terms of complete ablation, local recurrence, overall survival, and recent advances in RFA for liver malignancy.