Meta-Analysis
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Meta-Anal. Aug 28, 2022; 10(4): 220-237
Published online Aug 28, 2022. doi: 10.13105/wjma.v10.i4.220
Outcomes of microwave versus radiofrequency ablation for hepatocellular carcinoma: A systematic review and meta-analysis
Myo Jin Tang, Guy D Eslick, John S Lubel, Ammar Majeed, Avik Majumdar, William Kemp, Stuart K Roberts
Myo Jin Tang, John S Lubel, Ammar Majeed, William Kemp, Stuart K Roberts, Department of Gastroenterology, Alfred Hospital, Melbourne 3004, Victoria, Australia
Myo Jin Tang, Monash Medical School, Monash University, Melbourne 3004, Victoria, Australia
Guy D Eslick, Department of Statistics, Clued Pty Ltd, Sydney 2006, New South Wales, Australia
John S Lubel, Ammar Majeed, William Kemp, Stuart K Roberts, Central Clinical School, Monash University, Melbourne 3004, Victoria, Australia
Avik Majumdar, Department of Gastroenterology, Austin Hospital, Heidelberg 3084, Victoria, Australia
Avik Majumdar, Department of Medicine, Austin Campus, University of Medicine, Melbourne 3084, Victoria, Australia
Author contributions: Tang MJ performed the systematic review, acquisition and interpretation of the data, drafting the article, and final approval; Eslick GD performed the statistical analysis and interpretation of the data, drafting the article, and final approval; Lubel JS performed the systematic review, acquisition and interpretation of the data, drafting the article, and final approval; Majeed A performed interpretation of the data, review of the article, and final approval; Majumdar A contributed to the study design, interpretation of the data, review of the article, and final approval; Kemp W contributed to study concept and design, interpretation of the data, drafting and review of the article, and final approval; Roberts SK contributed to study concept and design, interpretation of the data, drafting and review of the article, and final approval.
Conflict-of-interest statement: All the authors declare that they have no conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Stuart K Roberts, FAASLD, AGAF, FRACP, MBBS, MD, Adjunct Professor, Department of Gastroenterology, Alfred Hospital, 99 Commercial Rd, Melbourne 3004, Victoria, Australia. s.roberts@alfred.org.au
Received: April 24, 2022
Peer-review started: April 24, 2022
First decision: June 19, 2022
Revised: July 1, 2022
Accepted: August 10, 2022
Article in press: August 10, 2022
Published online: August 28, 2022
Processing time: 124 Days and 1.8 Hours
Abstract
BACKGROUND

Studies to date comparing outcomes of microwave ablation (MWA) with radiofrequency ablation (RFA) on patients with hepatocellular carcinoma have yielded conflicting results, with no clear superiority of one technique over the other. The aim of this systematic review and meta-analysis was to compare the efficacy and safety of MWA with RFA.

AIM

To perform a systematic review and meta-analysis comparing the efficacy and safety of MWA with RFA.

METHODS

A systematic literature search was performed using Ovid Medline, Embase, PubMed, Reference Citation Analysis, Cochrane Central and Cochrane Systematic Review databases, and Web of Science. Abstracts and full manuscripts were screened for inclusion utilising predefined inclusion and exclusion criteria comparing outcomes of MWA and RFA. A random-effects model was used for each outcome. Meta-regression analysis was performed to adjust for the difference in follow-up period between the studies. Primary outcome measures included complete ablation (CA) rate, local recurrence rate (LRR), survival [local recurrence-free survival (LRFS), overall survival (OS)] and adverse events.

RESULTS

A total of 42 published studies [34 cohort and 8 randomised controlled trials (RCT)] with 6719 patients fulfilled the selection criteria. There was no significant difference in tumour size between the treatment groups. CA rates between MWA and RFA groups were similar in prospective cohort studies [odds ratio (OR) 0.95, 95% confidence interval (CI) 0.28–3.23] and RCTs (OR 1.18, 95%CI 0.64–2.18). However, retrospective studies reported higher rates with MWA (OR 1.29, 95%CI 1.06–1.57). Retrospective cohort studies reported higher OS (OR 1.54, 95%CI 1.15–2.05 and lower LRR (OR 0.67, 95%CI 0.51–0.87). No difference in terms of LRFS or 30-d mortality was observed between both arms. MWA had an increased rate of adverse respiratory events when compared to RFA (OR 1.99, 95%CI 1.07–3.71, P = 0.03).

CONCLUSION

MWA achieves similar CA rates and as good or better longer-term outcomes in relation to LRR and OS compared to RFA. Apart from an increased rate of respiratory events post procedure, MWA is as safe as RFA.

Keywords: Microwave ablation; Radiofrequency ablation; Hepatocellular carcinoma; Survival; Recurrence; Meta-analysis

Core Tip: Studies to date comparing outcomes of microwave ablation with radiofrequency ablation have yielded conflicting results, with no clear superiority of one technique over the other. To our knowledge, this is the most comprehensive study on this topic. A large cohort of 6719 patients were examined, enabling us to identify outliers and provide results with a smaller margin of error. The primary outcomes of this study were complete ablation, local recurrence rate, overall and local recurrence free survival and safety.