Irreversible Electroporation for Hepatic Tumors: Protocol Standardization Using the Modified Delphi Technique

Purpose: A consensus study of panelists was performed to provide a uniform protocol regarding (contra) indications, procedural parameters, perioperative care, and follow-up of irreversible electroporation (IRE) for the treatment of hepatic malignancies. Materials and Methods: Interventional radiologists who had 2 or more publications on IRE, reporting at least 1 patient cohort in the field of hepatobiliary IRE, were recruited. The 8 panelists were asked to anonymously complete 3 iterative rounds of IRE-focused questionnaires to collect data according to a modified Delphi technique. Consensus was defined as having reached 80% or greater agreement. Results: Panel members’ response rates were 88%, 75%, and 88% in rounds 1, 2, and 3, respectively; consensus was reached on 124 of 136 items (91%). Percutaneous or intraoperative hepatic IRE should be considered for unresectable primary and secondary malignancies that are truly unsuitable for thermal ablation because of proximity to critical structures. Absolute contraindications are ventricular arrhythmias, cardiac stimulation devices, and congestive heart failure of New York Heart Association class 3 or higher. A metal stent outside the ablation zone should not be considered a contraindication. For the only commercially available IRE device, the recommended settings are an inter-electrode distance of 10–20 mm and an exposure length of 20 mm. After 10 test pulses, 90 treatment pulses of 1500 V/cm should be delivered continuously, with a pulse length of 70–90 μs. The first post-procedural follow-up should take place 1 month after IRE and thereafter every 3 months, using cross-sectional imaging plus tumor marker assessment. Conclusions: This article provides recommendations, created by a modified Delphi consensus study, regarding patient selection, workup, procedure, and follow-up of IRE treatment for hepatic malignancies.