The Role of Focal Liver Ablation in the Treatment of Unresectable Primary and Secondary Malignant Liver Tumors

Surgical resection is often the first-line treatment option for primary and select metastatic hepatic malignancies. A minority of patients with hepatocellular carcinoma undergo potentially curative resection. Similarly, patients with liver-only metastasis are candidates for resection less than 15% of the time because of bilobar disease in which resection would sacrifice too great a volume of hepatic parenchyma, tumor proximity to major vascular or biliary structures thus preventing adequate margins, or unfavorable tumor biology. Ablative techniques directed at tumor elimination while minimizing injury to the surrounding functional hepatic parenchyma may be offered to select patients with unresectable cancers. Radiofrequency ablation, percutaneous ethanol injection, transarterial chemoembolization, cryoablation, microwave coagulation, and laser-induced interstitial thermotherapy all offer potential local tumor control and occasionally achieve long-term disease-free survival. This review focuses on the indications, anticipated benefits, and limitations of these ablative techniques.