1Department of Surgery, Harvard Medical School & Massachusetts General Hospital, Boston, MA, USA.
2Department of Surgery, Indiana University School of Medicine, I545 Barnhill Dr, EH541, Indianapolis, IN, 46202, USA.
3Department of Surgery, Texas Tech University Health Sciences, Lubbock, TX, USA.
4Department of Surgery, William Beaumont Army Medical Center, Fort Bliss, TX, USA.
5King George's Medical University, Chowk, Lucknow, India.
6Department of Surgery, University of California, San Francisco - East Bay, CA, USA.
7Jawaharlal Nehru Medical College and Hospital, Aligarh Muslim University, Aligarh, India.
8Division of Surgical Oncology, Department of Surgery, Emory University School of Medicine, Winship Cancer Institute, Atlanta, GA, USA.
9Department of Surgery, Alpert Medical School of Brown University, Providence, RI, USA.
10Knowledge Synthesis, University of Manitoba, Winnipeg, MB, Canada.
11Department of Surgery, University of Central Florida, Tampa, FL, USA.
12Department of Surgery, University of Sfax, Sfax, Tunisia.
13Sentara Medical Group, Norfolk, VA, USA.
14University of Texas Southwestern Medical Center, Dallas, TX, USA.
15Department of Surgery, Brooke Army Medical Center, Houston, TX, USA.
16Department of Surgery and Pediatrics, Tulane University, New Orleans, LA, USA.
17School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada.
18Department of Surgery, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, USA.
19Department of Surgery, University of Chicago, Chicago, IL, USA.
20Department of Surgery, University of Florida College of Medicine-Jacksonville, Jacksonville, FL, USA.
21Department of Surgery, Ochsner Clinic, New Orleans, LA, USA.
22Department of Surgery, University of California San Francisco, San Francisco, CA, USA.
23Department of Surgery, TCU and UNTHSC School of Medicine, Fort Worth, TX, USA.
24Department of Surgery, Indiana University School of Medicine, I545 Barnhill Dr, EH541, Indianapolis, IN, 46202, USA. firstname.lastname@example.org.
Background: Primary hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLM) represent the two most common malignant neoplasms of the liver. The objective of this study was to assess outcomes of surgical approaches to liver ablation comparing laparoscopic versus percutaneous microwave ablation (MWA), and MWA versus radiofrequency ablation (RFA) in patients with HCC or CRLM lesions smaller than 5 cm.
Methods: A systematic review was conducted across seven databases, including PubMed, Embase, and Cochrane, to identify all comparative studies between 1937 and 2021. Two independent reviewers screened for eligibility, extracted data for selected studies, and assessed study bias using the modified Newcastle Ottawa Scale. Random effects meta-analyses were subsequently performed on all available comparative data.
Results: From 1066 records screened, 11 studies were deemed relevant to the study and warranted inclusion. Eight of the 11 studies were at high or uncertain risk for bias. Our meta-analyses of two studies revealed that laparoscopic MW ablation had significantly higher complication rates compared to a percutaneous approach (risk ratio = 4.66; 95% confidence interval = [1.23, 17.22]), but otherwise similar incomplete ablation rates, local recurrence, and oncologic outcomes. The remaining nine studies demonstrated similar efficacy of MWA and RFA, as measured by incomplete ablation, complication rates, local/regional recurrence, and oncologic outcomes, for both HCC and CRLM lesions less than 5 cm (p > 0.05 for all outcomes). There was no statistical subgroup interaction in the analysis of tumors < 3 cm.
Conclusion: The available comparative evidence regarding both laparoscopic versus percutaneous MWA and MWA versus RFA is limited, evident by the few studies that suffer from high/uncertain risk of bias. Additional high-quality randomized trials or statistically matched cohort studies with sufficient granularity of patient variables, institutional experience, and physician specialty/training will be useful in informing clinical decision making for the ablative treatment of HCC or CRLM.