Dual and Single Switching Monopolar RFA Using Separable Clustered Electrode for Treatment of HCC

Radiofrequency Ablation Using a Separable Clustered Electrode for the Treatment of Hepatocellular Carcinomas: A Randomized Controlled Trial of a Dual-Switching Monopolar Mode Versus a Single-Switching Monopolar Mode

This study was conducted to prospectively compare the efficacy, safety and mid-term outcomes of dual-switching monopolar (DSM) radiofrequency ablation (RFA) with those of conventional single-switching monopolar (SSM) RFA in the treatment of hepatocellular carcinoma (HCC).

Recently, dual switching monopolar RFA (DSM-RFA) was developed to enhance further the efficiency of the single switching monopolar RFA (SSM-RFA) in creating ablation zone; Yoon et al. reported that DSM-RFA allowed significantly greater RF energy delivery to target tissue per given time, and then, created significantly larger ablation zone than the SSM-RFA in ex vivo and in vivo animal experiments. A retrospective comparative study by Choi et al. reported that the DSM-RFA created significantly larger ablation volume than, but seemed to show similar LTP rate to the SSM-RFA. Still, whether the physical differences between SSM-RFA and DSM-RFA translate into better clinical outcomes remains an open question. Regarding that the choice of equipment is an essential factor to consider in planning image-guided tumor ablation procedure, we thought that the prospective comparison between DSM-RFA and the SSM-RFA would be helpful for improving results of RFA. Therefore, the purpose of this study was to prospectively compare the efficacy, safety and mid-term outcomes of DSM-RFA with those of conventional SSM-RFA in the treatment of HCC.

RFA is performed in dual switching mode using a separable clustered electrode (Octopus®) and a three-channel dual-generator unit.

RFA is performed in single switching mode using a separable clustered electrode (Octopus®) and a three-channel dual-generator unit.

A separable clustered electrode is similar to a clustered electrode, although it differs from a conventional clustered electrode in that each individual electrode is separable.

Description and comparison of the type and incidence of major complication after RFA are assessed according to Society of Interventional Radiology (SIR) grading system in two groups.

Inclusion Criteria: Diagnosed with HCC (>= 1.5cm and < 5cm in maximal diameter) according to AASLD guideline or LI-RADS on MDCT or liver MRI within 60 days before RFA no history of previous locoregional treatment Exclusion Criteria: more than three HCC nodules tumors abutting to the central portal vein or hepatic vein with a diameter > 5 mm Child-Pugh class C tumors with major vascular invasion extrahepatic metastasis severe coagulopathy (platelet cell count of less than 50,000 cells/mm3 or INR prolongation of more than 50 %)