Advances in clinical application of cryoablation therapy for hepatocellular carcinoma and metastatic liver tumor.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Although surgical resection and liver transplantation are the curative treatments, many of HCC patients do not qualify for these curative therapies at the presentation. Thus, ablation therapies are currently important modalities in HCC treatment. Among currently available ablation therapies, cryoablation (ie, cryotherapy) is a novel local therapeutic modality. However, cryoablation has not been widely used as one of ablation therapies for HCC, because of historical concerns about risk of bleeding when cryotherapy is delivered by early generation of the argon-helium device. Nevertheless, with technological advances and increased clinical experience in the past decade, clinical application of cryoablation for HCC management has significantly increased. Accumulating data have demonstrated that cryoablation is highly effective in local tumor control with well-acceptable safety profile, and the overall survival is comparable with that of radiofrequency ablation in patients with tumors <5 cm. Compared with radiofrequency ablation and other thermal-based modalities, cryoablation has several advantages, such as the ability to produce larger and precise zones of ablation. This article systemically reviews the advances in clinical application of cryoablation therapy for HCC, including the related mechanisms and technology, clinical indications, efficacy and safety profiles, and future research directions.