Microwave ablation and radiofrequency ablation for the treatment of hepatocellular carcinoma: Result of the first prospective randomized controlled trial

Abstract

Introduction: Microwave ablation (MWA) has theoretical advantages over radiofrequency ablation (RFA): shorter ablation time, higher temperature of ablation, reduction of heat-sink effect and treatment of larger lesions. Due to lacking of prospective study assessing its efficacy,MWAis still not accepted for the treatment of hepatocellular carcinoma (HCC) as RFA is. In a prospective randomized multi-centric study, we compared rate of local tumor progression and survival in patients with chronic liver disease with HCC ≤4cm treated either byMWAor by RFA. Methods: Patients with chronic liver disease having HCC with ≤3 lesions of≤4cm, BCLC stage A, not eligible for surgery were prospectively randomized from 2011 to 2015. Final RFA group consisted in 73 patients with 104 lesions ablated (11 females, 53 patients with Child-Pugh A) and finalMWAgroup consisted in 71 patients with 98 lesions ablated (12 females, 57 patients with Child-Pugh A). Rate of local tumor progression (LTP) at one year in intention-to-treat analysis was the primary outcome. Time to progression (TTP), survival, incomplete treatment rate and safety constituted the secondary outcomes. Groups were compared using unpaired T-test and Chi-square test depending of the type of data. Survival analysis was made using Kaplan-Meier curves. Results: Patient groups were similar for demographic, biology and tumor characteristics (mean lesion size was 18mm in both groups). LTP at 1year follow up was not different between the two groups (RFA: LTP 2.8%;MWA: 5%, p=0.65) and even at more than 20 months follow up (RFA: LTP 8.6%; MWA: 7.1%, respectively, p=0.98). TTP was similar (RFA 15 months (SD:7) andMWA12 months (SD:8); p=0.48), confirmed by analysis with competition risk and inverse probability of censoring weighting analyses accounting for transplantation or death. Survival at 20 months was not different: RFA group 88.5%,MWAgroup 88.8% (p=0.88). Rate of complication was low with two grade 4 complications (SIR classification), both inMWAgroup. Conclusion: The first prospective randomized study with patients with HCC ≤4cm treated either by RFA orMWAevidenced no difference in local tumor progression and survival at more than 20 months of follow up.