Percutaneous ablation of hepatocellular carcinoma: state-of-the-art.

Percutaneous ablation is considered the best treatment option for patients with early-stage hepatocellular carcinoma (HCC) who are not candidates for surgical resection or liver transplantation. Several methods have been developed, including intratumoral injection of ethanol or acetic acid, and thermal ablation with radiofrequency, laser, microwaves, or cryosurgery. Percutaneous ethanol injection (PEI) has been the most widely used technique. Several series have provided indirect evidence that PEI improves the natural history of HCC. Patients with Child-Pugh class A cirrhosis and either a single tumor smaller than 5 cm or as many as three lesions each smaller than 3 cm may achieve a 5-year survival of 50%. The major limitation of PEI is the high local recurrence rate, which may reach 33-43%. Radiofrequency (RF) ablation has emerged as the most powerful alternate method for percutaneous ablation. Recent studies have shown that RF ablation can achieve more effective local tumor control than PEI with fewer treatment sessions. In a randomized trial, local recurrence-free survival rates were significantly higher in patients who received RF ablation than in those treated by PEI, and treatment allocation was confirmed as an independent prognostic factor by multivariate analysis. RF ablation could therefore be considered as the percutaneous treatment of choice for patients with early-stage tumors. Further investigation is warranted to clarify whether current RF technology could offer improved results in patients with intermediate-stage HCC.