Liver Function Tests Following Irreversible Electroporation of Liver Tumors: Experience in 174 Procedures

Irreversible electroporation (IRE) is a relatively new ablation modality that uses electric currents to cause cell death. It is commonly used to treat primary and secondary liver tumors in patients with normal liver function and preexisting cirrhosis. Retrospective analysis of 205 procedures sought to evaluate changes in liver function after IRE. Liver function tests (LFTs) results before and after IRE were evaluated from 174 procedures in 124 patients. Aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase (ALKP), and total bilirubin levels were analyzed. The study was Health Insurance Portability and Accountability Act compliant and institutional review board approved. Informed consent was waived. Changes in LFT results after IRE were compared with baseline and were followed up over time to see if they resolved. Changes were compared with volume of ablation. The greatest perturbations were in transaminase levels. The levels increased sharply within 24 hours after IRE in 129 (74.1%) procedures to extreme levels (more than 20 times the upper limit of normal in one-third of cases). Resolution occurred in 95% and was demonstrated to have occurred by a mean of approximately 10 weeks, many documented as early as 7 days after procedure. ALKP levels elevated in 10% procedures, was slower to increase, and was less likely to resolve. Total bilirubin level demonstrated 2 different patterns of elevation--early and late--and similar to ALKP, it was more likely to remain elevated. There was no increased risk in patients with cirrhosis or cholangiocarcinoma. There was no correlation of levels with volume of ablation. IRE results in significant abnormalities in LFT results, but in most of the cases, these are self-limiting, do not preclude treatment, and are similar to the changes seen after radiofrequency and cryoablation in the liver

Vessel Patency Post Irreversible Electroporation

The purpose of the study was to evaluate the effect of Irreversible Electroporation (IRE) on vessel patency in close proximity to the ablation zone.Between January 2010 and November 2013, 101 patients underwent percutaneous IRE procedures using the NanoKnife for primary and metastatic tumors in different organs. Age ranged from 24 to 83 years. A total of 129 lesions were treated. [liver (100), pancreas (18), kidney (3), pelvis (1), aorto-caval lymph nodes (2), adrenal (2), lung (1), retroperitoneal (1), surgical bed of a prior Whipple procedure (1)]. Post treatment contrast-enhanced CT and MRI scans were reviewed to evaluate caliber, patency, and flow defects of vessels in close proximity to the ablation zone (defined as vessels within 0–1 cm from the treatment zone).A total of 158 vessels were examined for patency on follow-up. The mean distance of the vessel from the treatment zone was 2.3 ± 2.5 mm. Ten vessels within the treatment zone were encased by tumor. Mean tumor size was 2.7 + 1.5 cm. Overall mean follow-up was 10.3 months. Abnormal vascular changes were noted in 7 of 158 (4.4 %) vessels. No significant association was found between distances from the treatment zone and presence of narrowing/thrombosis at the follow-up imaging. (Mann–Whitney U, p = 0.772; logistic regression: p = 0.593; odds ratio: 0.908; CI 0.637–1.294).This study demonstrates safety of IRE for the treatment of tumors near the large blood vessels and tumors already encasing the vessels. Further studies to substantiate these findings are essential to validate this crucial advantage of IRE

Safety and Efficacy of the PleurX Catheter for the Treatment of Malignant Ascites

Background: Malignant ascites is a common complication seen in association with various types of neoplastic processes. Due to high recurrence rates, patients may require multiple paracenteses, which have associated complications such as increased risk of bleeding, infection, pain, and volume and electrolyte depletion. Objective: This study evaluated the management of malignant ascites by placement of the PleurX® tunneled catheter system at a single center. Methods: This was a retrospective study of 38 patients who underwent PleurX catheter placement for refractory malignant ascites between February 2006 and March 2012 at our institution. Pretreatment characteristics and outcome measures were reported using descriptive statistics. Results: The population included 21 males and 17 females with a mean age of 60.6 years (range, 36–79 years) diagnosed with metastatic disease from a variety of primary malignancies, the most common of which was pancreatic cancer (10 patients). In 84% of patients (32/38) who were not lost to follow-up, mean survival time was 40.7 days (range 4–434 days). Technical success rate of catheter placement was 100%. Conclusions: The PleurX catheter can be used to manage malignant ascites in severely ill patients with metastatic cancer, with a high rate of procedural success and a low incidence of potentially serious adverse events, infections, or catheter-related complications

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

To describe an initial experience with irreversible electroporation (IRE) in patients with colorectal liver metastasis (CLM). 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. 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. Percutaneous IRE of CLM is feasible and safe. A new response evaluation system for colorectal cancer appears to be prognostic

Percutaneous Irreversible Electroporation for Downstaging and Control of Unresectable Pancreatic Adenocarcinoma

Treatment of unresectable locally advanced pancreatic cancer (LAPC) usually includes chemotherapy and/or radiation therapy in an attempt to downstage these tumors to the extent of resectability, but outcomes remain poor. Irreversible electroporation (IRE) is an ablative modality that may be useful in this population. The aim of this study was to evaluate the safety of percutaneous IRE in patients with pancreatic adenocarcinoma. IRE was performed in patients with pancreatic cancer whose tumors remained unresectable after, or who were intolerant of, standard therapy. The procedures were all done percutaneously under general anesthesia. Patients were then followed for adverse events, tumor response, and survival. Fifteen IRE procedures were performed in 14 patients (one was treated twice). Three patients had metastatic disease and 11 had LAPC. All patients had received chemotherapy previously, and 11 had received radiation. The median tumor size was 3.3 cm (range, 2.5–7 cm). Immediate and 24-hour postprocedural scans demonstrated patent vasculature in the treatment zone in all patients. Two patients underwent surgery 4 and 5 months after IRE, respectively. Both had margin-negative resections, and one had a pathologic complete response; both remain disease-free after 11 and 14 months, respectively. Complications included spontaneous pneumothorax during anesthesia (n = 1) and pancreatitis (n = 1), and both patients recovered completely. There were no deaths directly related to the procedure. All three patients with metastatic disease at IRE died from progression of their disease. Percutaneous IRE for pancreatic adenocarcinoma is feasible and safe. A prospective trial is being planned