Application of Irreversible Electroporation Ablation as Adjunctive Treatment for Margin Enhancement: Safety and Efficacy.

BACKGROUND

Irreversible electroporation (IRE) is a relatively new ablation technique utilized as focal therapy to target areas of significant tumor burden to ablate tumors in situ or improve margins of resection. Its application has largely been reported in the pancreas, liver, kidney, and prostate. Because locoregional therapy is becoming more common, IRE may be a reasonable alternative in additional situations if shown to be safe and efficacious. We have utilized IRE intraoperatively in highly selected patients for adjunctive treatment of primary and metastatic tumors at the time of surgical resection to achieve local control where an R1 resection is clinically felt to be likely. We hypothesize that IRE is a safe and effective adjuvant therapy. Our primary objective was to evaluate the safety of IRE with regard to the effects of other structures within the ablated zone. A secondary objective was to estimate local control rates of locally advanced tumors when IRE was used as an adjunct for margin enhancement.

METHODS

This is a retrospective chart review of a prospective database at a single tertiary institution. The study included patients receiving IRE from November 2013 through May 2016 at the time of resection of tumor resection for margin enhancement. Primary tumors included liver, pancreatic, retroperitoneal, extremity, and pelvic tumors. Patients undergoing treatment for palliation or in situ ablation were excluded.

RESULTS

Forty patients received IRE for margin enhancement. Median follow-up was 14 mo. Three patients (7.5%) had a local recurrence, and 12 (30%) had a distant recurrence. Adverse events possibly related to IRE are described.

CONCLUSIONS

Our institution demonstrated a low local recurrence rate of only 7.5% in patients treated with intraoperative IRE for margin enhancement. This may be a useful adjunct at the time of surgical resection to help achieve local control in difficult areas where an R1 resection is likely. This topic will require further investigation with prospective trials and longer follow-up.