Comparison of therapeutic effects between radiofrequency ablation and percutaneous microwave coagulation therapy for small hepatocellular carcinomas

Background:  Although thermal ablation therapies have gained fairly wide acceptance as an effective treatment for small hepatocellular carcinoma (HCC), there have been only a few clinical studies comparing the response to radiofrequency ablation (RFA) and percutaneous microwave coagulation therapy (PMCT). We evaluated the therapeutic efficacy and safety of these two procedures for the treatment of small HCC measuring ≤ 2 cm in diameter. Methods:  Thirty-four patients who had 37 nodules were treated by RFA and were compared with 49 patients (56 nodules) who underwent PMCT. Treatment was repeated until complete tumor necrosis was confirmed by contrast computed tomography (CT) scanning. The therapeutic efficacy and complications were retrospectively compared between the two procedures. Results:  (i) There were significantly fewer treatment sessions (P < 0.001) in the RFA group than in the PMCT group, but the necrotic area was significantly larger (P < 0.001) in the former group. (ii) The local recurrence rate was significantly lower (P = 0.031) after RFA than after PMCT, although the ectopic recurrence rate showed no significant difference. (iii) The cumulative survival rate was significantly higher (P = 0.018) after RFA than after PMCT. (iv) The incidence of pain and fever after treatment was significantly higher in the PMCT group. Bile duct injury, pleural effusion, and ascites were also significantly more common in the PMCT group. Conclusions:  RFA is more useful than PMCT for the treatment of small HCC because it is minimally invasive and achieves a low local recurrence rate, high survival rate, and extensive necrosis after only a few treatment sessions.