Irreversible electroporation for nonthermal tumor ablation in the clinical setting: a systematic review of safety and efficacy.

PURPOSE: To provide an overview of current clinical results of irreversible electroporation (IRE), a novel, nonthermal tumor ablation technique that uses electric pulses to induce cell death, while preserving structural integrity of bile ducts and vessels. METHODS: All in-human literature on IRE reporting safety or efficacy or both was included. All adverse events were recorded. Tumor response on follow-up imaging from 3 months onward was evaluated. RESULTS: In 16 studies, 221 patients had 325 tumors treated in liver (n = 129), pancreas (n = 69), kidney (n = 14), lung (n = 6), lesser pelvis (n = 1), and lymph node (n = 2). No major adverse events during IRE were reported. IRE caused only minor complications in the liver; however, three major complications were reported in the pancreas (bile leak [n = 2], portal vein thrombosis [n = 1]). Complete response at 3 months was 67%-100% for hepatic tumors (93%-100% for tumors o 3 cm). Pancreatic IRE combined with surgery led to prolonged survival compared with control patients (20 mo vs 13 mo) and significant pain reduction. CONCLUSIONS: In cases where other techniques are unsuitable, IRE is a promising modality for the ablation of tumors near bile ducts and blood vessels. This articles gives an extensive overview of the available evidence, which is limited in terms of quality and quantity. With the limitations of the evidence in mind, IRE of central liver tumors seems relatively safe without major complications, whereas complications after pancreatic IRE appear more severe. The available limited results for tumor control are generally good. Overall, the future of IRE for difficult-to-reach tumors appears promising.

Percutaneous irreversible electroporation for the treatment of colorectal cancer liver metastases with a proposal for a new response evaluation system.

PURPOSE: To describe an initial experience with irreversible electroporation (IRE) in patients with colorectal liver metastasis (CLM). MATERIALS AND METHODS: A retrospective analysis of patients undergoing IRE for the management of CLM was performed. Procedures were done percutaneously under general anesthesia. Patients were then followed for adverse events, tumor response, and survival. RESULTS: Between March 2010 and February 2013, 29 patients underwent percutaneous ablation of 58 tumors in 36 IRE sessions. Most patients (89%) had an absolute or relative contraindication to thermal ablation. The median age was 62 years, and the median time from diagnosis to IRE was 28 months. The median number of lesions treated per patient was two, and the median tumor size was 2.7 cm. Patients had received previous chemotherapy regimens (range, 1-5 per patient). A new Metabolic Imaging And Marker Integration response evaluation criteria was used for response assessment, and was a predictor of progression-free and overall survival. The 2-year progression-free survival rate was 18% (95% confidence interval, 0%-35%), and the 2-year overall survival rate was 62% (95% confidence interval, 37%-87%). Complications included arrhythmias (n = 1) and postprocedure pain (n = 1). Both patients recovered without sequelae. CONCLUSIONS: Percutaneous IRE of CLM is feasible and safe. A new response evaluation system for colorectal cancer appears to be prognostic.

Local treatment with deep percutaneous electrochemotherapy of different tumor lesions: pain relief and objective response results from an observational study.

OBJECTIVE: The aim of this investigation focuses on the evaluation of the efficacy of deep-seated Electrochemotherapy (ECT) in terms of pain relief and local objective response, in pre-treated patients with neither further available pharmacological treatments nor eligible for surgery. PATIENTS AND METHODS: Deep percutaneous ECT has been performed in 20 patients subjected to systemic anaesthesia. Bleomycin was administrated intravenously before the application of the electrical pulses on the target area, employing multiple single needles depending on the size and location of the target tumor. RESULTS: Pain assessment based on Visual Analogue Scale showed significant pain relief one month after treatment in all patients, reducing from 7.5 to 3 as a median value (p-value at Wilcoxon test <0.001). Local symptom-free survival median value was 5.5 months. At the first follow-up (1-2 months), a local disease control rate (LDCR) was observed in 19/20 (95%) patients: complete responses in 2 (10%), partial responses in 8 (40%) and stable disease in 9 (45%). Local progression-free survival median value was 5.7 months. Overall, no major adverse effects were observed. CONCLUSIONS: Our study indicates that deep percutaneous ECT can produce a significant pain reduction and a high LDCR in different tumor lesions, for anatomical site or histotype. In particular, ECT has demonstrated to be effective in various histotypes and deep-seated tumor lesions never treated before by this approach giving a new chance to physicians for reducing oncological pain in patients not eligible to other therapeutic routes. The innovative peculiarity of our study was the successful application of deep percutaneous ECT on adrenal metastasis, malignant pleural mesothelioma, uterine leiomyosarcoma and the uncommon case of a male müllerian tumor.