Comparison of Microwave and Radiofrequency Ablation for the Treatment of Small- and Medium-Sized Hepatocellular Carcinomas in a Prospective Randomized Trial

Purpose To compare the therapeutic response and clinical outcome of CT-guided percutaneous microwave (MWA) and radiofrequency ablation (RFA) for the treatment of small- and medium-sized HCC. Materials and Methods In this prospective trial, 50 patients with HCC were randomly assigned to MWA or RFA treatment. MRI was performed 24 h before and after ablation and subsequently in 3-month intervals. Ablation volumes, ablation durations, adverse events (AE), technique efficacy, technical success, local tumor progression (LTP), disease-free survival (DFS), intrahepatic distant recurrence (IDR), and overall survival (OS) rates were evaluated. Results The mean ablation volume was 66.5 cm³ for MWA and 29.2 cm³ for RFA (p < 0.01). The mean ablation durations for MWA and RFA were 11.2 ± 4.0 min and 16.3 ± 4.7 min, respectively (p < 0.01). Six mild AEs were documented (p > 0.05). All treatments had a technical success rate and a technique efficacy rate of 100 % (50/50, p = 1.00). LTP within 2 years occurred in 1/25 (4 %) in the MWA group and in 4/25 (16 %) in the RFA group (p = 0.06). IDR within 2 years was 8/25 (32 %) for MWA and 14/25 (56 %) for RFA (p < 0.05). The median DFS was 24.5 months and 13.4 months for MWA and RFA, respectively (p = 0.02). The 1-, 2-, 3-year OS rates were 100 %, 80 %, 72 % in the MWA group and 72 %, 64 %, 60 % in the RFA group, respectively (p ≥ 0.14). Conclusion The clinical outcome after MWA or RFA for HCC treatment was very similar with no significant differences in LTP or OS. However, MWA shows a trend toward better DFS with fewer IDRs than RFA. Key Points: