Value of CT-Guided Percutaneous Irreversible Electroporation Added to FOLFIRINOX Chemotherapy in Locally Advanced Pancreatic Cancer: A Post Hoc Comparison.

PURPOSE: To compare survival after CT-guided percutaneous irreversible electroporation (IRE) and folinic acid, fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) chemotherapy versus FOLFIRINOX only in patients with locally advanced pancreatic cancer (LAPC). MATERIALS AND METHODS: A post hoc comparison was performed of data derived from a prospective IRE-FOLFIRINOX cohort and a retrospective FOLFIRINOX-only cohort. All patients received a minimum of 3 cycles of FOLFIRINOX for LAPC and were considered eligible for CT-guided percutaneous IRE. Endpoints included overall survival (OS), local and distant progression-free survival, and time to progression (TTP) and were compared using stratified Kaplan-Meier analysis. Patients who received > 8 cycles of FOLFIRINOX before IRE and who had tumors > 6 cm in the FOLFIRINOX-only group were excluded. RESULTS: Of 103 patients with a diagnosis of LAPC, 52 were deemed eligible (n = 30 IRE-FOLFIRINOX and n = 22 FOLFIRINOX-only). Patients in the FOLFIRINOX-only arm had larger tumors (53 mm ± 19 vs 38 mm ± 7, P = .340), had more locoregional lymph node metastases (23% vs 7%, P = .622), and more often received radiotherapy (7 patients vs 2 patients, P = .027); all other baseline characteristics were comparable. Median OS was 17.0 months (range, 5-35 mo; SD = 6) for IRE-FOLFIRINOX versus 12.4 months (range, 3-22 mo; SD = 6) for FOLFIRINOX-only (P = .038). After sensitivity analyses, median OS was 17.2 months (range, 6-27 mo; SD = 6) versus 12.4 months (range, 7-32 mo; SD = 10) (P = .05). Median TTP was longer in the IRE-FOLFIRINOX group: 14.2 months (range, 5-25 mo; SD = 4) versus 5.2 months (range, 2-22; SD = 6) (P = .0001). CONCLUSIONS: In patients with LAPC after FOLFIRINOX chemotherapy, CT-guided percutaneous IRE may improve OS and TTP. This study may facilitate the design of randomized controlled trials to compare survival after IRE-FOLRINOX versus FOLFIRINOX-only.

HyCHEED System for Maintaining Stable Temperature Control during Preclinical Irreversible Electroporation Experiments at Clinically Relevant Temperature and Pulse Settings.

Electric permeabilization of cell membranes is the main mechanism of irreversible electroporation (IRE), an ablation technique for treatment of unresectable cancers, but the pulses also induce a significant temperature increase in the treated volume. To investigate the therapeutically thermal contribution, a preclinical setup is required to apply IRE at desired temperatures while maintaining stable temperatures. This study's aim was to develop and test an electroporation device capable of maintaining a pre-specified stable and spatially homogeneous temperatures and electric field in a tumor cell suspension for several clinical-IRE-settings. A hydraulically controllable heat exchange electroporation device (HyCHEED) was developed and validated at 37 °C and 46 °C. Through plate electrodes, HyCHEED achieved both a homogeneous electric field and homogenous-stable temperatures; IRE heat was removed through hydraulic cooling. IRE was applied to 300 µL of pancreatic carcinoma cell suspension (Mia PaCa-2), after which cell viability and specific conductivity were determined. HyCHEED maintained stable temperatures within ±1.5 °C with respect to the target temperature for multiple IRE-settings at the selected temperature levels. An increase of cell death and specific conductivity, including post-treatment, was found to depend on electric-field strength and temperature. HyCHEED is capable of maintaining stable temperatures during IRE-experiments. This provides an excellent basis to assess the contribution of thermal effects to IRE and other bio-electromagnetic techniques.

Added value of CA19-9 response in predicting resectability of locally advanced pancreatic cancer following induction chemotherapy.

BACKGROUND: Determining the resectability of locally advanced pancreatic cancer (LAPC) after induction chemotherapy is complex since CT-imaging cannot accurately portray tumor response. We hypothesized that CA19-9 response adds to RECIST-staging in predicting resectability of LAPC. METHODS: Post-hoc analysis within a prospective study on LAPC (>90° arterial or >270° venous involvement). CA19-9 response was determined after induction chemotherapy. Surgical exploration was performed in RECIST-stable or -regressive disease. The relation between CA19-9 response, resectability and survival was assessed. RESULTS: Restaging in 54 patients with LAPC after induction chemotherapy (mostly FOLFIRINOX) identified 6 RECIST-regressive, 32 RECIST-stable, and 16 patients with RECIST-progressive disease. The resection rate was 20.3% (11/54 patients). Sensitivity and specificity of RECIST-regression for resection were 40% and 87% whereas the positive predictive value (PPV) and negative predictive value (NPV) were 67% and 68%. Using a 30% decrease of CA19-9 as cut-off, 9/10 patients were correctly classified as resectable (90% sensitivity, PPV 43%) and 3/15 as unresectable (20% specificity, NPV 75%). In the total cohort, a CA19-9 decrease ≥30% was associated with improved survival (22.4 vs. 12.7 months, p = 0.02). CONCLUSION: Adding CA19-9 response after induction chemotherapy seems useful in determining which patients with RECIST non-progressive LAPC should undergo exploratory surgery.

Ablation of Locally Advanced Pancreatic Cancer with Percutaneous Irreversible Electroporation: Results of the Phase I/II PANFIRE Study.

Purpose To (a) investigate the safety of percutaneous irreversible electroporation (IRE) for locally advanced pancreatic cancer and (b) evaluate the quality of life (QOL), pain perception, and efficacy in terms of time to local progression, event-free survival, and overall survival (OS). Materials and Methods The study was approved by the local review board (NL42888.029.13). All patients provided written informed consent for study participation, the ablation procedure, and data usage. Between January 2014 and June 2015, 25 patients with histologically proved locally advanced pancreatic cancer 5 cm or smaller (13 women, 12 men; median age, 61 years; age range, 41-78 years) were prospectively included to undergo percutaneous computed tomographic-guided IRE. Patients with a metallic biliary Wallstent, epilepsy, or ventricular arrhythmias were excluded. Kaplan-Meier estimates were used to investigate time to local progression, event-free survival, and OS. Safety was assessed on the basis of adverse events, which were graded according to the Common Terminology Criteria for Adverse Events. Pain perception and QOL were evaluated by using specific questionnaires. Results All patients underwent IRE. The median largest tumor diameter was 4.0 cm (range, 3.3-5.0 cm). After a median follow-up of 12 months (interquartile range: 7-16 months), median event-free survival after IRE was 8 months (95% confidence interval [CI]: 4 months, 12 months); the median time to local progression after IRE was 12 months (95% CI: 8 months, 16 months). The median OS was 11 months from IRE (95% CI: 9 months, 13 months) and 17 months from diagnosis (95% CI: 10 months, 24 months). There were 12 minor complications (grade I or II) and 11 major complications (nine grade III, two grade IV) in 10 patients. There were no deaths within 90 days after IRE. Conclusion Percutaneous IRE for locally advanced pancreatic cancer is generally well tolerated, although major adverse events can occur. Preliminary survival data are encouraging and support the setup of larger phase II and III clinical trials to assess the efficacy of IRE plus chemotherapy in the neoadjuvant and adjuvant or second-line setting compared with more widely adopted regimens such as chemotherapy and/or radiation therapy. © RSNA, 2016 Online supplemental material is available for this article.

Induction Chemotherapy Followed by Resection or Irreversible Electroporation in Locally Advanced Pancreatic Cancer (IMPALA): A Prospective Cohort Study.

BACKGROUND: Following induction chemotherapy, both resection or irreversible electroporation (IRE) may further improve survival in patients with locally advanced pancreatic cancer (LAPC). However, prospective studies combining these strategies are currently lacking, and available studies only report on subgroups that completed treatment. This study aimed to determine the applicability and outcomes of resection and IRE in patients with nonprogressive LAPC after induction chemotherapy. METHODS: This was a prospective, single-center cohort study in consecutive patients with LAPC (September 2013 to March 2015). All patients were offered 3 months of induction chemotherapy (FOLFIRINOX or gemcitabine depending on performance status), followed by exploratory laparotomy for resection or IRE in patients with Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 nonprogressive, IRE-eligible tumors. RESULTS: Of 132 patients with LAPC, 70% (n = 93) started with chemotherapy (46% [n = 61] FOLFIRINOX). After 3 months, 59 patients (64%) had nonprogressive disease, of whom 36 (27% of the entire cohort) underwent explorative laparotomy, resulting in 14 resections (11% of the entire cohort, 39% of the explored patients) and 15 IREs (11% of the entire cohort, 42% of the explored patients). After laparotomy, 44% (n = 16) of patients had Clavien-Dindo grade 3 or higher complications, and 90-day all-cause mortality was 11% (n = 4). With a median follow-up of 24 months, median overall survival after resection, IRE, and for all patients with nonprogressive disease without resection/IRE (n = 30) was 34, 16, and 15 months, respectively. The resection rate in 61 patients receiving FOLFIRINOX treatment was 20%. CONCLUSION: Induction chemotherapy followed by IRE or resection in nonprogressive LAPC led to resection or IRE in 22% of all-comers, with promising survival rates after resection but no apparent benefit of IRE, despite considerable morbidity. Registered at Netherlands Trial Register (NTR4230).

Systematic Review of Resection Rates and Clinical Outcomes After FOLFIRINOX-Based Treatment in Patients with Locally Advanced Pancreatic Cancer.

BACKGROUND: FOLFIRINOX prolongs survival in patients with metastatic pancreatic cancer and may also benefit patients with locally advanced pancreatic cancer (LAPC). Furthermore, it may downstage a proportion of LAPC into (borderline) resectable disease, however data are lacking. This review assessed outcomes after FOLFIRINOX-based therapy in LAPC. METHODS: The PubMed, EMBASE and Cochrane library databases were systematically searched for studies published to 31 August 2015. Primary outcome was the (R0) resection rate. RESULTS: Fourteen studies involving 365 patients with LAPC were included; three studies administered a modified FOLFIRINOX regimen. Of all patients, 57 % (n = 208) received radiotherapy. The pooled resection rate was 28 % (n = 103, 77 % R0), with a perioperative mortality of 3 % (n = 2), and median overall survival ranged from 8.9 to 25.0 months. Survival data after resection were scarce, with only one study reporting a median overall survival of 24.9 months in 28 patients. A complete pathologic response was found in 6 of 85 (7 %) resected specimens. Dose reductions were described in up to 65 % of patients, grade 3-4 toxicity occurred in 23 % (n = 51) of patients, and 2 % (n = 5) had to discontinue treatment. Data of patients treated solely with FOLFIRINOX, without additional radiotherapy, were available from 292 patients: resection rate was 12 % (n = 29, 70 % R0), with 15.7 months median overall survival and 19 % (n = 34) grade 3-4 toxicity. CONCLUSIONS: Outcomes after FOLFIRINOX-based therapy in patients with LAPC seem very promising but further prospective studies are needed, especially with regard to survival after resection.

Thermal Energy during Irreversible Electroporation and the Influence of Different Ablation Parameters.

PURPOSE: Irreversible electroporation (IRE) uses high-voltage electric fields to achieve cell death. Although the mechanism of IRE is mainly designated as nonthermal, development of secondary Joule heating is inevitable. The study purpose was to gain understanding of temperature development and distribution during IRE. MATERIALS AND METHODS: IRE was performed in a transparent polyacrylamide gel resembling soft tissue. Mechanical effects, changes in temperature gradient, and absolute temperature changes were measured with three different optical techniques (high-speed, color Schlieren, and infrared imaging) to investigate the effect on temperature of variations in voltage, pulse length, active tip length (ATL), interelectrode distance, electrode configuration (parallel, convergent, and divergent), and sequential pulsing (pulse delivery interrupted by breaks). The total delivered energy was calculated. RESULTS: A temperature gradient, starting at the tips of both electrodes and expanding toward each other, developed immediately with pulse delivery. Temperatures increased with increasing voltage (by 2.5°C-40.4°C), pulse length (by 5.3°C-9.8°C), ATL (by 5.9°C-17.6°C), and interelectrode distance (by 7.6°C-21.5°C), in accordance with higher energy delivery. Nonparallel electrode placement resulted in heterogeneous temperature distribution with the peak temperature focused in the area with the shortest interelectrode distance. Sequential pulse delivery significantly reduced the temperature increase compared with continuous pulsing (4.3°C vs 11.7°C). CONCLUSIONS: Voltage, pulse length, interelectrode distance, ATL, and electrode configuration each have a strong effect on temperature development and distribution during IRE. Sequential pulsing reduces the extent and volume of thermal distribution and may prove beneficial with respect to procedural safety.

Thermodynamic profiling during irreversible electroporation in porcine liver and pancreas: a case study series.

AIMS: First, the aim of the study was to determine whether irreversible electroporation (IRE) is associated with heat generation in the liver and pancreas at clinical (≤1,500 V/cm) and supraclinical (>1,500 V/cm) electroporation settings; second, to assess the risk of thermal tissue damage in and adjacent to the treated volume in highly perfused versus moderately perfused parts of both organs; third, to investigate the influence of perfusion and of the presence and the orientation of a metal stent on the maximal thermal elevation (ΔTSession,max) in the tissue during an IRE session at fixed IRE settings, and finally, to determine whether the maximum temperature elevation within the IRE-subjected organ during an IRE treatment (single or multiple sessions) is reflected in the organ's surface temperature. METHODS: The aims were investigated in 12 case studies conducted in five female Landrace pigs. Several IRE settings were applied for lateral (2), triangular (3), and rectangular (4) electrode configurations in the liver hilum, liver periphery, pancreas head, and pancreas tail. IRE series of 10-90 pulses were applied with pulse durations that varied from 70 µs to 90 µs and electric field strengths between 1,200 V/cm and 3,000 V/cm. In select cases, a metal stent was positioned in the bile duct at the level of the liver hilum. Temperatures were measured before, during, and after IRE in and adjacent to the treatment volumes using fiber optical temperature probes (temperature at the nucleation centers) and digital thermography (surface temperature). The occurrence of thermal damage was assumed to be at temperatures above 50 °C (ΔTSession,max ≥ 13 °C relative to body temperature of 37 °C). The temperature fluctuations at the organ surface (ΔTLocSurf) were compared to the maximum temperature elevation during an IRE treatment in the electroporation zone. In select cases, IRE was applied to tissue volumes encompassing the portal vein (PV) and a constricted and patent superior mesenteric vein (SMV) to determine the influence of the heatsink effect of PV and SMV on ΔTSession,max. RESULTS: The median baseline temperature was 31.6 °C-36.3 °C. ΔTSession,max ranged from -1.7 °C to 25.5 °C in moderately perfused parts of the liver and pancreas, and from 0.0 °C to 5.8 °C in highly perfused parts. The median ΔTLocSurf of the liver and pancreas was 1.0 °C and 10.3 °C, respectively. Constricting the SMV in the pancreas head yielded a 0.8 °C higher ΔTSession,max. The presence of a metal stent in the liver hilum resulted in a ΔTSession,max of 19.8 °C. Stents parallel to the electrodes caused a ΔTSession,max difference of 4.2 °C relative to the perpendicular orientation. CONCLUSIONS: Depending on IRE settings and tissue type, IRE is capable of inducing considerable heating in the liver and pancreas that is sufficient to cause thermal tissue damage. More significant temperature elevations are positively correlated with increasing number of electrode pairs, electric field strength, and pulse number. Temperature elevations can be further exacerbated by the presence and orientation of metal stents. Temperature elevations at the nucleation centers are not always reflected in the organ's surface temperature. Heat sink effects caused by large vessels were minimal in some instances, possibly due to reduced blood flow caused by anesthesia. RELEVANCE FOR PATIENTS: Appropriate IRE settings must be chosen based on the tissue type and the presence of stents to avoid thermal damage in healthy peritumoral tissue and to protect anatomical structures [Table: see text].

Time-Dependent Impact of Irreversible Electroporation on Pathology and Ablation Size in the Porcine Liver: A 24-Hour Experimental Study.

Irreversible electroporation causes cell death through low frequency, high voltage electrical pulses and is increasingly used to treat non-resectable cancers. A recent systematic review revealed that tissue damage through irreversible electroporation is time-dependent, but the impact of time on the ablation zone size remains unknown. Irreversible electroporation ablations were performed hourly during 24 consecutive hours in the peripheral liver of 2 anaesthetized domestic pigs using clinical treatment settings. Immediately after the 24th ablation, the livers were harvested and examined for tissue response in time based on macroscopic and microscopic pathology. The impact of time on these outcomes was assessed with Spearman rank correlation test. Ablation zones were sharply demarcated as early as 1 hour after treatment. During 24 hours, the ablation zones showed a significant increase in diameter (rs = 0.493, P = .014) and total surface (rs = 0.499, P = .013), whereas the impact of time on the homogeneous ablated area was not significant (rs = 0.172, P = .421). Therefore, the increase in size could mainly be attributed to an increase in the transition zone. Microscopically, the ablation zones showed progression in cell death and inflammation. This study assessed the dynamics of irreversible electroporation on the porcine liver during 24 consecutive hours and found that the pathological response (ie, cell death/inflammation), and ablation size continue to develop for at least 24 hours. Consequently, future studies on irreversible electroporation should prolong their observation period.

Locally Advanced Pancreatic Cancer: Work-Up, Staging, and Local Intervention Strategies.

Locally advanced pancreatic cancer (LAPC) has several definitions but essentially is a nonmetastasized pancreatic cancer, in which upfront resection is considered not beneficial due to extensive vascular involvement and consequent high chance of a nonradical resection. The introduction of FOLFIRINOX chemotherapy and gemcitabine-nab-paclitaxel (gem-nab) has had major implications for the management and outcome of patients with LAPC. After 4-6 months induction chemotherapy, the majority of patients have stable disease or even tumor-regression. Of these, 12 to 35% are successfully downstaged to resectable disease. Several studies have reported a 30-35 months overall survival after resection; although it currently remains unclear if this is a result of the resection or the good response to chemotherapy. Following chemotherapy, selection of patients for resection is difficult, as contrast-enhanced computed-tomography (CT) scan is unreliable in differentiating between viable tumor and fibrosis. In case a resection is not considered possible but stable disease is observed, local ablative techniques are being studied, such as irreversible electroporation, radiofrequency ablation, and stereotactic body radiation therapy. Pragmatic, multicenter, randomized studies will ultimately have to confirm the exact role of both surgical exploration and ablation in these patients. Since evidence-based guidelines for the management of LAPC are lacking, this review proposes a standardized approach for the treatment of LAPC based on the best available evidence.

Ablation with irreversible electroporation in patients with advanced perihilar cholangiocarcinoma (ALPACA): a multicentre phase I/II feasibility study protocol.

INTRODUCTION: The majority of patients with perihilar cholangiocarcinoma (PHC) has locally advanced disease or distant lymph node metastases on presentation or exploratory laparotomy, which makes them not eligible for resection. As the prognosis of patients with locally advanced PHC or lymph node metastases in the palliative setting is significantly better compared with patients with organ metastases, ablative therapies may be beneficial. Unfortunately, current ablative options are limited. Photodynamic therapy causes skin phototoxicity and thermal ablative methods, such as stereotactic body radiation therapy and radiofrequency ablation, which are affected by a heat/cold-sink effect when tumours are located close to vascular structures, such as the liver hilum. These limitations may be overcome by irreversible electroporation (IRE), a relatively new ablative method that is currently being studied in several other soft tissue tumours, such as hepatic and pancreatic tumours. METHODS AND ANALYSIS: In this multicentre phase I/II safety and feasibility study, 20 patients with unresectable PHC due to vascular or distant lymph node involvement will undergo IRE. Ten patients who present with unresectable PHC will undergo CT-guided percutaneous IRE, whereas ultrasound-guided IRE will be performed in 10 patients with unresectable tumours detected at exploratory laparotomy. The primary outcome is the total number of clinically relevant complications (Common Terminology Criteria for Adverse Events, score of≥3) within 90 days. Secondary outcomes include quality of life, tumour response, metal stent patency and survival. Follow-up will be 2 years. ETHICS AND DISSEMINATION: The protocol has been approved by the local ethics committees. Data and results will be submitted to a peer-reviewed journal. CONCLUSION: The Ablation with irreversible eLectroportation in Patients with Advanced perihilar CholangiocarcinomA (ALPACA) study is designed to assess the feasibility of IRE for advanced PHC. The main purpose is to inform whether a follow-up trial to evaluate safety and effectiveness in a larger cohort would be feasible.

Minimally invasive versus open distal pancreatectomy (LEOPARD): study protocol for a randomized controlled trial.

BACKGROUND: Observational cohort studies have suggested that minimally invasive distal pancreatectomy (MIDP) is associated with better short-term outcomes compared with open distal pancreatectomy (ODP), such as less intraoperative blood loss, lower morbidity, shorter length of hospital stay, and reduced total costs. Confounding by indication has probably influenced these findings, given that case-matched studies failed to confirm the superiority of MIDP. This accentuates the need for multicenter randomized controlled trials, which are currently lacking. We hypothesize that time to functional recovery is shorter after MIDP compared with ODP even in an enhanced recovery setting. METHODS: LEOPARD is a randomized controlled, parallel-group, patient-blinded, multicenter, superiority trial in all 17 centers of the Dutch Pancreatic Cancer Group. A total of 102 patients with symptomatic benign, premalignant or malignant disease will be randomly allocated to undergo MIDP or ODP in an enhanced recovery setting. The primary outcome is time (days) to functional recovery, defined as all of the following: independently mobile at the preoperative level, sufficient pain control with oral medication alone, ability to maintain sufficient (i.e. >50%) daily required caloric intake, no intravenous fluid administration and no signs of infection. Secondary outcomes are operative and postoperative outcomes, including clinically relevant complications, mortality, quality of life and costs. DISCUSSION: The LEOPARD trial is designed to investigate whether MIDP reduces the time to functional recovery compared with ODP in an enhanced recovery setting. TRIAL REGISTRATION: Dutch Trial Register, NTR5188 . Registered on 9 April 2015.

The Influence of a Metal Stent on the Distribution of Thermal Energy during Irreversible Electroporation.

PURPOSE: Irreversible electroporation (IRE) uses short duration, high-voltage electrical pulses to induce cell death via nanoscale defects resulting from altered transmembrane potential. The technique is gaining interest for ablations in unresectable pancreatic and hepatobiliary cancer. Metal stents are often used for palliative biliary drainage in these patients, but are currently seen as an absolute contraindication for IRE due to the perceived risk of direct heating of the metal and its surroundings. This study investigates the thermal and tissue viability changes due to a metal stent during IRE. METHODS: IRE was performed in a homogeneous tissue model (polyacrylamide gel), without and with a metal stent placed perpendicular and parallel to the electrodes, delivering 90 and 270 pulses (15-35 A, 90 µsec, 1.5 cm active tip exposure, 1.5 cm interelectrode distance, 1000-1500 V/cm, 90 pulses/min), and in-vivo in a porcine liver (4 ablations). Temperature changes were measured with an infrared thermal camera and with fiber-optic probes. Tissue viability after in-vivo IRE was investigated macroscopically using 5-triphenyltetrazolium chloride (TTC) vitality staining. RESULTS: In the gel, direct stent-heating was not observed. Contrarily, the presence of a stent between the electrodes caused a higher increase in median temperature near the electrodes (23.2 vs 13.3°C [90 pulses]; p = 0.021, and 33.1 vs 24.8°C [270 pulses]; p = 0.242). In-vivo, no temperature difference was observed for ablations with and without a stent. Tissue examination showed white coagulation 1mm around the electrodes only. A rim of vital tissue remained around the stent, whereas ablation without stent resulted in complete tissue avitality. CONCLUSION: IRE in the vicinity of a metal stent does not cause notable direct heating of the metal, but results in higher temperatures around the electrodes and remnant viable tissue. Future studies should determine for which clinical indications IRE in the presence of metal stents is safe and effective.

Recent Advances in Pancreatic Cancer Surgery of Relevance to the Practicing Pathologist.

Recent advances in pancreatic surgery have the potential to improve outcomes for patients with pancreatic cancer. We address 3 new, trending topics in pancreatic surgery that are of relevance to the pathologist. First, increasing awareness of the prognostic impact of intraoperatively detected extraregional and regional lymph node metastases and the international consensus definition on lymph node sampling and reporting. Second, neoadjuvant chemotherapy, which is capable of changing 10% to 20% of initially unresectable, to resectable disease. Third, in patients who remain unresectable following neoadjuvant chemotherapy, local ablative therapies may change indications for treatment and improve outcomes.

Percutaneous irreversible electroporation of locally advanced pancreatic carcinoma using the dorsal approach: a case report.

Irreversible electroporation (IRE) is a novel image-guided ablation technique that is increasingly used to treat locally advanced pancreatic carcinoma (LAPC). We describe a 67-year-old male patient with a 5 cm stage III pancreatic tumor who was referred for IRE. Because the ventral approach for electrode placement was considered dangerous due to vicinity of the tumor to collateral vessels and duodenum, the dorsal approach was chosen. Under CT-guidance, six electrodes were advanced in the tumor, approaching paravertebrally alongside the aorta and inferior vena cava. Ablation was performed without complications. This case describes that when ventral electrode placement for pancreatic IRE is impaired, the dorsal approach could be considered alternatively.

A nationwide comparison of laparoscopic and open distal pancreatectomy for benign and malignant disease.

BACKGROUND: Cohort studies from expert centers suggest that laparoscopic distal pancreatectomy (LDP) is superior to open distal pancreatectomy (ODP) regarding postoperative morbidity and length of hospital stay. But the generalizability of these findings is unknown because nationwide data on LDP are lacking. STUDY DESIGN: Adults who had undergone distal pancreatectomy in 17 centers between 2005 and 2013 were analyzed retrospectively. First, all LDPs were compared with all ODPs. Second, groups were matched using a propensity score. Third, the attitudes of pancreatic surgeons toward LDP were surveyed. The primary outcome was major complications (Clavien-Dindo grade ≥III). RESULTS: Among 633 included patients, 64 patients (10%) had undergone LDP and 569 patients (90%) had undergone ODP. Baseline characteristics were comparable, except for previous abdominal surgery and mean tumor size. In the full cohort, LDP was associated with fewer major complications (16% vs 29%; p = 0.02) and a shorter median [interquartile range, IQR] hospital stay (8 days [7-12 days] vs 10 days [8-14 days]; p = 0.03). Of all LDPs, 33% were converted to ODP. Matching succeeded for 63 LDP patients. After matching, the differences in major complications (9 patients [14%] vs 19 patients [30%]; p = 0.06) and median [IQR] length of hospital stay (8 days [7-12 days] vs 10 days [8-14 days]; p = 0.48) were not statistically significant. The survey demonstrated that 85% of surgeons welcomed LDP training. CONCLUSIONS: Despite nationwide underuse and an impact of selection bias, outcomes of LDP seemed to be at least noninferior to ODP. Specific training is welcomed and could improve both the use and outcomes of LDP.