Percutaneous Image-Guided Irreversible Electroporation for the Treatment of Unresectable, Locally Advanced Pancreatic Adenocarcinoma.

PURPOSE: To describe safety and effectiveness of percutaneous irreversible electroporation (IRE) for treatment of unresectable, locally advanced pancreatic adenocarcinoma (LAPC). MATERIALS AND METHODS: This retrospective study included 50 patients (23 women, 27 men; age range, 46-91 y; median age, 62.5 y) with biopsy-proven, unresectable LAPC who received percutaneous computed tomography (CT)-guided IRE. The primary objective was to assess the safety profile of the procedure; the secondary objective was to determine overall survival (OS). All patients had prior chemotherapy (1-5 lines, median 2), and 30 (60%) of 50 patients had prior radiation therapy. Follow-up included CT at 1 month and at 3-month intervals thereafter. RESULTS: There were no treatment-related deaths and no 30-day mortality. Serious adverse events occurred in 10 (20%) of 50 patients (abdominal pain [n = 7], pancreatitis [n = 1], sepsis [n = 1], gastric leak [n = 1]). Median OS was 27.0 months (95% confidence interval [CI], 22.7-32.5 months) from time of diagnosis and 14.2 months (95% CI, 9.7-16.2 months) from time of IRE. Patients with tumors ≤ 3 cm (n = 24) had significantly longer median OS than patients with tumors > 3 cm (n = 26): 33.8 vs 22.7 months from time of diagnosis (P = .002) and 16.2 vs 9.9 months from time of IRE (P = .031). Tumor size was confirmed as the only independent predictor of OS at multivariate analysis. CONCLUSIONS: Percutaneous image-guided IRE of unresectable LAPC is associated with an acceptable safety profile.

Pilot Study of Intrahepatic Artery Chemotherapy in Combination with Sorafenib in Hepatocellular Carcinoma.

BACKGROUND/AIM: Sorafenib and chemoembolization of the liver (TACE) have both produced increased survival in hepatocellular carcinoma (HCC). Some patients cannot tolerate TACE due to portal vein thrombosis or risk of liver failure. In this pilot trial, we aimed to combine intrahepatic infusion (IA) of cisplatin or carboplatin with sorafenib for unresectable HCC. PATIENTS AND METHODS: Patients with Child's A or early B received IA cisplatin or carboplatin every 6 weeks with oral sorafenib. MRI/CT scans were performed every 6 weeks. RESULTS: Eleven patients were accrued. Of 10 evaluable patients, 6 had clinical benefit (4 partial responses for 2+, 3+, 8+ and 18 months, 2 minor responses). Two patients were down-staged enough for ablation therapy or liver transplant and remain free of disease for 32+ and 36+ months. Toxicity was generally tolerable. CONCLUSION: Preliminary results are encouraging and this combination may down-stage some patients with unresectable disease.

Current diagnosis and management of post-transjugular intrahepatic portosystemic shunt refractory hepatic encephalopathy.

Transjugular intrahepatic portosystemic shunt has evolved into an important option for management of complications of portal hypertension. The use of polytetrafluoroethylene covered stents enhances shunt patency. Hepatic encephalopathy (HE) remains a significant problem after TIPS placement. The approach to management of patients with refractory hepatic encephalopathy typically requires collaboration between different specialties. Patient selection for TIPS requires careful evaluation of risk factors for HE. TIPS procedure-related technical factors like stent size, attention to portosystemic pressure gradient reduction and use of adjunctive variceal embolization maybe important. Conservative medical therapy in combination with endovascular therapies often results in resolution or substantial reduction of symptoms. Liver transplantation is, however, the ultimate treatment.

Is Antibiotic Prophylaxis for Percutaneous Radiofrequency Ablation (RFA) of Primary Liver Tumors Necessary? Results From a Single-Center Experience.

PURPOSE: The purpose of this study was to evaluate need for antibiotic prophylaxis for radiofrequency ablation (RFA) of liver tumors in patients with no significant co-existing risk factors for infection. MATERIALS AND METHODS: From January 2004 to September 2013, 83 patients underwent 123 percutaneous RFA procedures for total of 152 hepatocellular carcinoma (HCC) lesions. None of the patients had pre-existing biliary enteric anastomosis (BEA) or any biliary tract abnormality predisposing to ascending biliary infection or uncontrolled diabetes mellitus. No pre- or post-procedure antibiotic prophylaxis was provided for 121 procedures. Data for potential risk factors were reviewed retrospectively and analyzed for the frequency of infectious complications, including abscess formation. RESULTS: One patient (1/121 (0.8%) RFA sessions) developed a large segment 5 liver abscess/infected biloma communicating with the gallbladder 7 weeks after the procedure, successfully treated over 10 weeks with IV and PO antibiotic therapy and percutaneous catheter drainage. This patient did not receive any antibiotics prior to RFA. During the procedure, there was inadvertent placement of RFA probe tines into the gallbladder. No other infectious complications were documented. CONCLUSION: These data suggest that the routine use of prophylactic antibiotics for liver RFA is not necessary in majority of the patients undergoing liver ablation for HCC and could be limited to patients with high-risk factors such as the presence of BEA or other biliary abnormalities, uncontrolled diabetes mellitus, and large centrally located tumors in close proximity to central bile ducts. Larger randomized studies are needed to confirm this hypothesis.

Vessel patency post irreversible electroporation.

PURPOSE: The purpose of the study was to evaluate the effect of Irreversible Electroporation (IRE) on vessel patency in close proximity to the ablation zone. MATERIALS AND METHODS: 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). RESULTS: 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). CONCLUSION: 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.

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.

Pain analysis in patients with hepatocellular carcinoma: irreversible electroporation versus radiofrequency ablation-initial observations.

PURPOSE: To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). METHODS: This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher's exact test, the Chi-square test, and Student's t test. RESULTS: There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. CONCLUSION: IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

Percutaneous irreversible electroporation for downstaging and control of unresectable pancreatic adenocarcinoma.

PURPOSE: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: Percutaneous IRE for pancreatic adenocarcinoma is feasible and safe. A prospective trial is being planned.

A renal protocol for all ages and all indications: mercapto-acetyl-triglycine (MAG3) with simultaneous injection of furosemide (MAG3-F0): a 17-year experience.

Current clinical requirements mandate the existence of a renal diuretic protocol, which is fast and easy, applicable in all ages and for all indications, convenient for both the patient and the technologist, and provides diagnostic as well as prognostic information. Seventeen years ago a 25-minute protocol, after oral hydration, with no bladder catheterization, and simultaneous injection of mercapto-acetyl-triglycine (MAG(3)) and furosemide (MAG(3)-F(0)), was initiated. It initially was used for the evaluation of drainage and emerged as a protocol to also evaluate the renal parenchyma. Results of this protocol have been published individually, per clinical application. MAG(3)-F(0) was instrumental in the evaluation and prognosis of congenital disorders. For obstruction, in the newborn, an increasing renogram mandates intervention, whereas a downsloping one predicts spontaneous resolution. In children or adults, preoperatively or postoperatively, when the cortex was visualized and drained normally, there was no obstruction, even if urine was retained within a dilated collecting system or an extrarenal pelvis. For diseases of the renal parenchyma, the protocol enabled the diagnosis of acute pyelonephritis (APN) revealing the "regional parenchymal dysfunction," diagnostic of APN. Diffuse parenchymal diseases were characterized by increased residual cortical activity (RCA), and their progression was manifested as a deterioration of RCA. End-stage renal disease was characterized by lack of accumulation and retention. Trauma and leaks were identified with specific patterns. In renovascular hypertension (RVH), an increase in RCA after angiotension-converting enzyme inhibitors is diagnostic of RVH and prognostic of the beneficial effect of angioplasty on hypertension. In renal colic, stratification was possible into (1) complete or severe obstruction requiring immediate intervention, (2) mild obstruction allowing waiting, (3) spontaneous decompression (stunned kidney), and (4) no recent obstruction. In transplants, it enabled differentiation of acute tubular necrosis, acute or chronic rejection and nephrotoxicity, and identified infarcts, RVH, leaks and obstruction. Finally, this method allows for a quick semiquantification of renal function. The clinical usefulness of the MAG(3)-F(0) protocol in most congenital or acquired renal problems is proven through long-term clinical experience and has resulted in a substantial utilization of the test at our Center.

Role of angiography in popliteal artery entrapment syndrome.

Popliteal artery entrapment syndrome (PAES) is a rare but potentially limb-threatening disease seen predominantly in young athletes. We present an 18- year-old female avid soccer player, who complained of severe pain in both calves for over a year. Clinical examination and laboratory data were not helpful for diagnosis. Magnetic resonance imaging of both knees was inconclusive. Diagnostic angiography demonstrated bilateral, smooth and focal narrowing of both popliteal arteries only on active flexion and extension. PAES was confirmed by surgery. Our case is unique because of female gender and functional PAES. A review of the literature regarding PAES and its clinical relevance is presented.

Endovascular management of superior mesenteric artery pseudoaneurysm and fistula.

The uncommon presentation of an arterioportal fistula (APF) involving the superior mesenteric artery (SMA) associated with a pseudoaneurysm represents a therapeutic challenge. We present the case of a 24-year-old female admitted to the hospital after multiple gunshot wounds to the abdomen; the patient underwent multiple surgeries and, in the process, developed a SMA pseudoaneurysm and fistula. The vascular interventional radiology team was consulted for treatment of the pseudoaneurysm and fistula. A covered stent was inserted percutaneously to exclude the APF and the pseudoaneurysm in a single procedure. The patient returned to our service after 21 months for a follow-up CT scan, which demonstrated the stent and the distal vasculature to be patent.

Use of D-STAT to prevent bleeding following percutaneous transhepatic intraportal islet transplantation.

An infrequent but nevertheless concerning complication associated with percutaneous transhepatic islet transplantation is bleeding. Historically in 61 procedures at this institution, we experienced four bleeding complications in three patients (6.6%), two requiring blood transfusion (3.3%) and two asymptomatic intraperitoneal bleeds detected sonographically at 24 h postprocedure (3.3%). It is suggested that the source of the majority of these bleeds is the liver parenchymal tract following removal of the infusion catheter combined with a significant dose of heparin administered to prevent portal vein thrombosis. Various techniques have been used to reduce the risk of tract bleeding, including gelfoam, intravascular coils, and cautery. In our experience gelfoam alone has been used to plug the catheter tract (n = 47); however, in the aforementioned three patients, this technique failed, either due to dislodgement of, or bleeding peripheral to, the plug. This article describes the use of D-Stat, a collagen/thrombin paste that is injected into the peripheral tract. In five consecutive cases performed using D-Stat, there has been no bleeding or thromboses detected. D-Stat combined with a single gelfoam plug offers a quick, easy, efficacious way of sealing the entire catheter tract without leaving any permanent hardware in the liver. This new method may simplify tract closure and reduce bleeding complications in islet transplantation.

Arteriovenous malformation mimicking a renal-cell carcinoma.

We describe a renal arteriovenous malformation in a patient with a 1-month history of flank pain. Imaging studies were interpreted as being consistent with renal-cell carcinoma. However, Doppler ultrasonography demonstrated turbulent blood flow, and selective renal angiography confirmed the diagnosis of an arteriovenous malformation. Embolization relieved the pain. This case calls attention to the need to consider arteriovenous malformations in the differential diagnosis of central homogenously enhancing renal lesions.