Irreversible electroporation of unresectable soft tissue tumors with vascular invasion: effective palliation

Abstract

BackgroundIrreversible electroporation (IRE) has recently been added as an additional therapeutic ablative option in patients with locally advanced cancers (LAC) involving vital structures. IRE delivers localized electric current by peri-tumoral discrete probes to attain irreversible changes in cell membrane leading to cell death. The aim of this study was to evaluate the long-term effects of IRE in the treatment of locally advanced tumors.MethodsA prospective IRB approved evaluation of 107 consecutive patients from 7 institutions with tumors that had vascular invasion treated with IRE from 5/2010 to 1/2012. LAC was defined as primary tumor with <5 mm from major vascular structure based on pre-operative dynamic imaging or intra-operative criteria.ResultsIRE as utilized in LAC in the liver (N = 42, 40%) and pancreas (N = 37, 35%), with a median number of lesions being 2 with a mean target size of 3 cm. IRE attributable morbidity rate was 13.3% (total 29.3%) with high-grade complications seen in 4.19% (total 12.6%). No significant vascular complications were seen, and of the high-grade complications, bleeding (2), biliary complications (3) and DVT/PE (3) were the most common. Complications were more likely with pancreatic lesions (p = 0.0001) and open surgery (p = 0.001). Calculated local recurrence free survival (LRFS) was 12.7 months with a median follow up of 26 months censured at last follow up. The tumor target size was inversely associated with recurrence free survival (b = 0.81, 95% CI: 1.6 to 4.7, p value = 0.02) but this did not have a significant overall survival impact.ConclusionsIRE represents a novel therapeutic option in patients with LAC involving vital structures that are not amenable to surgical resection. Acceptable to high local disease control and the long LRFS can be achieved with this therapy in combination with other multi-disciplinary therapies.

Irreversible electroporation for nonthermal tumor ablation in patients with hepatocellular carcinoma: initial clinical experience in Japan

“…For these reasons, IRE is an attractive treatment option for various soft tissue tumors located in challenging locations [3].…”

Treatment of 200 Locally Advanced (Stage III) Pancreatic Adenocarcinoma Patients With Irreversible Electroporation

“…This unique method of action has allowed for IRE to be successfully utilized in the palliative treatment of LAPC safely, with surprisingly prolonged survival. 1,2,6,7 Recent advances in multimodality therapy of stage 3 LAPC have included chemotherapy, surgery, and/or radiation therapy. Surgical resection of LAPC in combination with multimodality treatment remains the optimal treatment option based on the improved overall survival in reported cases.…”

Safety and Feasibility of Irreversible Electroporation (IRE) in Patients with Locally Advanced Pancreatic Cancer: Results of a Prospective Study

“…Several studies on the in vivo potential applications of IRE for solid tumors (e.g., lung, liver, kidney, and pancreas) have been published [17,18,19,20,21,22,23]. Martin et al showed that IRE is a suitable option for LAPC with encouraging preliminary results in terms of safety and feasibility, local-progression-free survival, distant progression-free survival and overall survival [24,25].…”