Multibipolar radiofrequency vs single needle microwave ablation for the treatment of newly diagnosed hepatocellular carcinoma.

BACKGROUND: Data comparing the outcomes of hepatocellular carcinoma (HCC) ablation by multibipolar radiofrequency ablation (mbp-RFA) and microwave ablation (MWA) are lacking. This study compares safety and efficacy of the two techniques in treatment-naive HCC. AIM: To compare the risk of local tumor progression (LTP) according to the technique; secondary endpoints included technique efficacy rate at one-month, overall survival and major complication rate. METHODS: A bi-institutional retrospective analysis of patients undergoing treatment-naive HCC ablation by either technique was performed. Inverse probability of treatment weighting was used to compare the two groups. Mixed effects multivariate Cox regression was applied to identify risk factors for LTP. RESULTS: A total of 362 patients (mean age, 66.1 ± 6.2 years, 308 men) were included, of which 242 (323 tumors) treated by mbp-RFA and 120 (168 tumors) by MWA. After a median follow-up of 27 months, cumulative LTP was 11.4% after mbp-RFA and 25.2% after MWA. Independent risk factors for LTP at multivariate analysis were MWA (hazard ratio = 2.85, P < 0.001) and tumor size (hazard ratio = 1.08, P < 0.001). Two-year LTP-free survival was higher after mbp-RFA than MWA regardless of size (< 3 cm: 96% vs 87.1%, P < 0.01; ≥ 3 cm: 87.5% vs 74%, P = 0.04). Technique efficacy rate was higher after mbp-RFA (94.1% vs 87.5%, P = 0.01). No difference was observed in major complication rate (9.5% vs 7.5%, P = 0.59), nor 5-year overall survival (63.6% vs 58.3%, P = 0.33). CONCLUSION: Mbp-RFA leads to better local tumor control of treatment-naïve HCC than MWA regardless of tumor size and has better primary efficacy, while maintaining a comparable safety profile.