Ablation of hepatic malignant tumors with irreversible electroporation: A systematic review and meta-analysis of outcomes

BACKGROUND: Irreversible electroporation (IRE) ablation is a new technique that is used to eliminate malignant tumors through nonthermal approaches. OBJECTIVE: The purpose of this review was to evaluate the efficiency of IRE for hepatic malignant tumors. METHODS: A systematic search was performed from PubMed, Embase, Web of science, Scopus and other potential literatures from references in relevant articles July 26th, 2016. Overall estimates of pooled standard mean difference (SMD) with 95% confidence interval (CI) were calculated for the changes of the pre- and post-IRE longest diameter, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and serum total bilirubin levels. Sensitivity analysis and publication bias and were performed after the pooled analysis, and the quality of the included literatures was appraised using Newcastle-Ottawa Scale (NOS). RESULTS: We finally included 300 patients (mean age: 51 to 66.6 years; male: 182; female: 118) from 9 studies of hepatic malignant tumors. The meta-analysis showed that comparing with the initial values, the longest diameter of the tumors was significantly decreased at the last follow-up months after IRE. Furthermore, the ALP, AST and total bilirubin levels were increased at 1 day after IRE while returned to baseline at the last follow-up month. No risk of publication bias was found, and all literatures were assessed good quality according to NOS. CONCLUSIONS: The pooled data indicated that IRE could be a minimal invasive and effective approach for patients who had preoperative poor liver function or those whose masses were in refractory locations where surgical resection was unsuitable.