Effectiveness of Microwave Ablation of Hepatocellular Carcinoma as Compared to Radiofrequency Ablation

The purpose of this study is to compare microwave ablation using the Acculis Microwave Tissue Ablation (MTA) System with conventional radiofrequency ablation (RFA) using Covidien cool-tip radiofrequency needle in patients with localized unresectabe hepatocelluar carcinoma (HCC). The investigators hypothesize that microwave ablation can achieve a better complete ablation rate as compared to radiofrerquency ablation. A randomized comparative study is performed by randomly assigned participants to microwave ablation arm or radiofrequency ablation arm. The efficacy of treatment outcome is assessed by the complete tumor ablation rate at 1 month, recurrence rate and survival time of participants. Safety of the procedures is also compared between the 2 treatment arms.