Therapeutic efficacy of percutaneous radiofrequency ablation versus microwave ablation for hepatocellular carcinoma

The aim of this study was to investigate the therapeutic efficacy of percutaneous radiofrequency (RF) ablation versus microwave (MW) ablation for hepatocellular carcinoma (HCC) measuring ≤ 5 cm in greatest diameter. From January 2006 to December 2006, 78 patients had undergone RF ablation whereas 77 had undergone MW ablation. Complete ablation (CA), local tumour progression (LTP) and distant recurrence (DR) were compared. The overall survival curves were calculated with the Kaplan-Meier technique and compared with the log-rank test. The CA rate was 83.4% (78/93) for RF ablation and 86.7%(91/105 for MW ablation. The LTP rate was 11.8% (11/93) for RF ablation and 10.5% (11/105) for MW ablation. DR was found in 51 (65.4%) in the RF ablation and 62 (80.5%) in the MW ablation. There was no significant difference in the 1-, 3-, and 5-year overall survival rates (P = 0.780) and the 1-, 3-, and 5-year disease-free survival rates (P = 0.123) between RF and MW ablation. At subgroup analyses, for patients with tumors ≤ 3.0 cm, there was no significant difference in the 1-, 3-, and 5-year overall survival rates (P = 0.067) and the corresponding disease-free survival rates(P = 0.849). For patients with tumor diameters of 3.1-5.0 cm, the 1-, 3-, and 5-year overall survival rates were 87.1%, 61.3%, and 40.1% for RF ablation and 85.4%, 36.6%, and 22% for MW ablation, with no significant difference (P = 0.068). The corresponding disease-free survival rates were 74.2%, 54.8%, and 45.2% for the RF ablation group and 53.3%, 26.8%, and 17.1% for the MW ablation group. The disease-free survival curve for the RF ablation group was significantly better than that for the MW ablation group (P = 0.018). RF ablation and MW ablation are both effective methods in treating hepatocellular carcinomas, with no significant differences in CA, LTP, DR, and overall survival.