Robotic Approach for Perihilar Cholangiocarcinoma IIIA Type: Step-by-Step Procedure.

BACKGROUND: Perihilar cholangiocarcinoma is a challenging technique to be performed by minimally invasive approach being the type III among the most complex procedure. Nowadays, the robotic approach is gaining increasing interest among the surgical community, and more and more series describing robotic liver resection have been reported. However, few cases of minimally invasive Bismuth type IIIA cholangiocarcinoma have been reported. Robotic approach allows for a better dissection and suture thanks to the flexible and precise instruments movements, overcoming some of the limitations of the laparoscopic technique. Therefore, robotic technique can facilitate some of the critical steps of a technically demanding procedure, such as the extended right hepatectomy for perihilar cholangiocarcinoma Bismuth IIIA type. METHODS: In this multimedia video we describe, for the first time in the literature, a full robotic surgical step-by-step technique with some tips and tricks for treating a perihilar cholangiocarcinoma Bismuth IIIA type, performing a radical extended right hemihepatectomy, including segment I combined with regional lymphadenectomy anf left bile duct reconstruction. A 55-year-old woman with obstructive jaundice (10 mg/dl) was referred to our center. The endobiliary brushing confirmed adenocarcinoma, and MRI/CT showed a focal perihilar lesion of 2 cm, including the main biliary duct bifurcation and extending up to the right duct (Bismuth Type IIIA hilar cholangiocarcinoma). After endoscopic biliary stents placement and 6 weeks after right portal vein embolization, the future liver remnant, including segments II and III, reached an enough hypertrophy volume with a ratio of 30%. A right hemihepatectomy with caudate lobe, including standard standard lymphadenectomy and left biliary duct reconstruction was performed. RESULTS: The operation lasted 670 min with an estimated blood loss of 350 ml. Postoperative pathological examination revealed a moderately differentiated adenocarcinoma pT1N0 with 15 retrieved nodes and free margins. The patient experienced a type A biliary fistula and was discharged on the 21st postoperative day without abdominal drainage. CONCLUSIONS: Through the tips and tricks presented in this multimedia article, we show the advantages of the robotic approach for performing correctly one of the most complex surgeries.1-7.

Levels of Robotic Mesopancreas Dissection According to Malignancy and Vascular Anatomy: What Surgeons Need to Know.

INTRODUCTION: The robotic approach is attracting increasing interest among the surgical community, and more and more series describing robotic pancreatoduodenectomy have been reported. Thus, surgeons performing robotic pancreatoduodenectomy should be confident with this critical step's potential scenarios. MATERIALS AND METHODS: According to Yosuke et al., there are three different levels of mesopancreas dissection. We describe the main steps for a safe mesopancreas dissection by robotic approach. RESULTS: This multimedia article provides, for the first time in literature, a comprehensive step-by-step overview of the mesopancreas dissection during robotic pancreatoduodenectomy (PD) and its three different levels according to tumor type. CONCLUSIONS: Through the tips and indications presented in this multimedia article, we aim to familiarize surgeons with the mesopancreas dissections levels according to type of malignancy and vascular anatomy.

Minimally Invasive Left Hepatectomy: Choosing the Suitable Surgical Strategy.

BACKGROUND: Numerous surgical techniques are currently available for minimally invasive left hepatic resection, each offering its own advantages and disadvantages. PATIENTS AND METHODS: This multimedia manuscript delves into the primary approaches for minimally invasive left hepatectomy, with a focus on particular topics such as left hepatic vein approach, transection and middle hepatic vein exposure, and Glissonean approach. We examine key factors that surgeons should consider when choosing among these methods and provide practical recommendations. RESULTS: To enhance understanding, our article includes video footage from multiple centres, showcasing expertly executed surgeries for each approach along with their main considerations. CONCLUSIONS: This multimedia resource will serve as a valuable guide for surgeons, aiding in the selection of the most suitable strategy for minimally invasive left hepatectomies, tailored to the specific needs of the patient and the characteristics of the lesion.

Cost-effectiveness of robotic vs laparoscopic distal pancreatectomy. Results from the national prospective trial ROBOCOSTES.

INTRODUCTION: Although several studies report that the robotic approach is more costly than laparoscopy, the cost-effectiveness of robotic distal pancreatectomy (RDP) over laparoscopic distal pancreatectomy (LDP) is still an issue. This study evaluates the cost-effectiveness of the RDP and LDP approaches across several Spanish centres. METHODS: This study is an observational, multicenter, national prospective study (ROBOCOSTES). For one year from 2022, all consecutive patients undergoing minimally invasive distal pancreatectomy were included, and clinical, QALY, and cost data were prospectively collected. The primary aim was to analyze the cost-effectiveness between RDP and LDP. RESULTS: During the study period, 80 procedures from 14 Spanish centres were analyzed. LDP had a shorter operative time than the RDP approach (192.2 min vs 241.3 min, p = 0.004). RDP showed a lower conversion rate (19.5% vs 2.5%, p = 0.006) and a lower splenectomy rate (60% vs 26.5%, p = 0.004). A statistically significant difference was reported for the Comprehensive Complication Index between the two study groups, favouring the robotic approach (12.7 vs 6.1, p = 0.022). RDP was associated with increased operative costs of 1600 euros (p < 0.031), while overall cost expenses resulted in being 1070.92 Euros higher than the LDP but without a statistically significant difference (p = 0.064). The mean QALYs at 90 days after surgery for RDP (0.9534) were higher than those of LDP (0.8882) (p = 0.030). At a willingness-to-pay threshold of 20,000 and 30,000 euros, there was a 62.64% and 71.30% probability that RDP was more cost-effective than LDP, respectively. CONCLUSIONS: The RDP procedure in the Spanish healthcare system appears more cost-effective than the LDP.

Outcomes After Minimally Invasive Versus Open Total Pancreatectomy: A Pan-European Propensity Score Matched Study.

OBJECTIVE: To assess postoperative 90-day outcomes after minimally invasive (laparoscopic/robot-assisted) total pancreatectomy (MITP) in selected patients versus open total pancreatectomy (OTP) among European centers. BACKGROUND: Minimally invasive pancreatic surgery is becoming increasingly popular but data on MITP are scarce and multicenter studies comparing outcomes versus OTP are lacking. It therefore remains unclear if MITP is a valid alternative. METHODS: Multicenter retrospective propensity-score matched study including consecutive adult patients undergoing MITP or OTP for all indications at 16 European centers in 7 countries (2008-2017). Patients after MITP were matched (1:1, caliper 0.02) to OTP controls. Missing data were imputed. The primary outcome was 90-day major morbidity (Clavien-Dindo ≥3a). Secondary outcomes included 90-day mortality, length of hospital stay, and survival. RESULTS: Of 361 patients (99MITP/262 OTP), 70 MITP procedures (50 laparoscopic, 15 robotic, 5 hybrid) could be matched to 70 OTP controls. After matching, MITP was associated with a lower rate of major morbidity (17% MITP vs. 31% OTP, P = 0.022). The 90-day mortality (1.4% MITP vs. 7.1% OTP, P = 0.209) and median hospital stay (17 [IQR 11-24] MITP vs. 12 [10-23] days OTP, P = 0.876) did not differ significantly. Among 81 patients with PDAC, overall survival was 3.7 (IQR 1.7-N/A) versus 0.9 (IQR 0.5-N/ A) years, for MITP versus OTP, which was nonsignificant after stratification by T-stage. CONCLUSION: This international propensity score matched study showed that MITP may be a valuable alternative to OTP in selected patients, given the associated lower rate of major morbidity.

Superior Mesenteric Artery First Approach for Minimally Invasive Pancreaticoduodenectomy: A Step-By-Step Surgical Technique Video.

INTRODUCTION: In the past decade, minimally invasive pancreaticoduodenectomy has been gaining interest. However, minimally invasive pancreaticoduodenectomy remains technically challenging and is associated with a steep learning curve. Additionally, the operating surgeon should be cognizant of replicating the same oncological steps as observed in the typical open approach. In view of this, there exist various maneuvers that are designed to achieve negative margins and a safer mesopancreatic dissection. One of these techniques is the superior mesenteric artery first approach, which is garnering interest among pancreatic surgeons. MATERIAL AND METHODS: According to existing literature, there are several superior mesenteric artery dissections approaches. We describes 5 different minimally invasive approaches. RESULTS: This multimedia manuscript provide, for the first time in literature, a comprehensive step-by-step overview of the superior mesenteric artery first approach for minimally invasive pancreaticoduodenectomy by a team of expert surgeons from various international institutions. CONCLUSIONS: Through the tips and indications presented in this article, we aim to guide the choice of this approach according to tumor location, type of minimally invasive approach and the operating surgeon's experience and increase familiarity with such a complex procedure.

Robot-Assisted Versus Laparoscopic Distal Pancreatectomy in Patients with Resectable Pancreatic Cancer: An International, Retrospective, Cohort Study.

BACKGROUND: Robot-assisted distal pancreatectomy (RDP) is increasingly used as an alternative to laparoscopic distal pancreatectomy (LDP) in patients with resectable pancreatic cancer but comparative multicenter studies confirming the safety and efficacy of RDP are lacking. METHODS: An international, multicenter, retrospective, cohort study, including consecutive patients undergoing RDP and LDP for resectable pancreatic cancer in 33 experienced centers from 11 countries (2010-2019). The primary outcome was R0-resection. Secondary outcomes included lymph node yield, major complications, conversion rate, and overall survival. RESULTS: In total, 542 patients after minimally invasive distal pancreatectomy were included: 103 RDP (19%) and 439 LDP (81%). The R0-resection rate was comparable (75.7% RDP vs. 69.3% LDP, p = 0.404). RDP was associated with longer operative time (290 vs. 240 min, p < 0.001), more vascular resections (7.6% vs. 2.7%, p = 0.030), lower conversion rate (4.9% vs. 17.3%, p = 0.001), more major complications (26.2% vs. 16.3%, p = 0.019), improved lymph node yield (18 vs. 16, p = 0.021), and longer hospital stay (10 vs. 8 days, p = 0.001). The 90-day mortality (1.9% vs. 0.7%, p = 0.268) and overall survival (median 28 vs. 31 months, p = 0.599) did not differ significantly between RDP and LDP, respectively. CONCLUSIONS: In selected patients with resectable pancreatic cancer, RDP and LDP provide a comparable R0-resection rate and overall survival in experienced centers. Although the lymph node yield and conversion rate appeared favorable after RDP, LDP was associated with shorter operating time, less major complications, and shorter hospital stay. The specific benefits associated with each approach should be confirmed by multicenter, randomized trials.

Is occlusion of the main pancreatic duct by thermal ablation really safe? A surgical innovation assessed according to IDEAL recommendations.

INTRODUCTION: Pre-clinical studies suggest that thermal ablation of the main pancreatic duct (TAMPD) is more recommendable than glue for reducing postoperative pancreatic fistula (POPF). Our aims were (1) to analyze the changes in the pancreas of patients after TAMPD and (2) to correlate the clinical findings with those obtained from a study on an animal model. MATERIALS AND METHODS: A retrospective early feasibility study of a marketed device for a novel clinical application was carried out on a small number of subjects (n = 8) in whom TAMPD was conducted to manage the pancreatic stump after a pancreatectoduodenectomy (PD). Morphological changes in the remaining pancreas were assessed by computed tomography for 365 days after TAMPD. RESULTS: All the patients showed either Grade A or B POPF, which generally resolved within the first 30 days. The duct's maximum diameter significantly increased after TAMPD from 1.5 ± 0.8 mm to 8.6 ± 2.9 mm after 7 days (p = .025) and was then reduced to 2.6 ± 0.8 mm after 365 days PO (p < .0001). The animal model suggests that TAMPD induces dilation of the duct lumen by enzymatic digestion of ablated tissue after a few days and complete exocrine atrophy after a few weeks. CONCLUSIONS: TAMPD leads to long-term exocrine pancreatic atrophy by completely occluding the duct. However, the ductal dilatation that occurred soon after TAMPD could even favor POPF, which suggests that TAMPD should be conducted several weeks before PD, ideally by digestive endoscopy.

Use and outcome of minimally invasive pancreatic surgery in the European E-MIPS registry.

BACKGROUND: The European registry for minimally invasive pancreatic surgery (E-MIPS) collects data on laparoscopic and robotic MIPS in low- and high-volume centers across Europe. METHODS: Analysis of the first year (2019) of the E-MIPS registry, including minimally invasive distal pancreatectomy (MIDP) and minimally invasive pancreatoduodenectomy (MIPD). Primary outcome was 90-day mortality. RESULTS: Overall, 959 patients from 54 centers in 15 countries were included, 558 patients underwent MIDP and 401 patients MIPD. Median volume of MIDP was 10 (7-20) and 9 (2-20) for MIPD. Median use of MIDP was 56.0% (IQR 39.0-77.3%) and median use of MIPD 27.7% (IQR 9.7-45.3%). MIDP was mostly performed laparoscopic (401/558, 71.9%) and MIPD mostly robotic (234/401, 58.3%). MIPD was performed in 50/54 (89.3%) centers, of which 15/50 (30.0%) performed ≥20 MIPD annually. This was 30/54 (55.6%) centers and 13/30 (43%) centers for MIPD respectively. Conversion rate was 10.9% for MIDP and 8.4% for MIPD. Overall 90 day mortality was 1.1% (n = 6) for MIDP and 3.7% (n = 15) for MIPD. CONCLUSION: Within the E-MIPS registry, MIDP is performed in about half of all patients, mostly using laparoscopy. MIPD is performed in about a quarter of patients, slightly more often using the robotic approach. A minority of centers met the Miami guideline volume criteria for MIPD.

Benchmarking of robotic and laparoscopic spleen-preserving distal pancreatectomy by using two different methods.

BACKGROUND: Benchmarking is an important tool for quality comparison and improvement. However, no benchmark values are available for minimally invasive spleen-preserving distal pancreatectomy, either laparoscopically or robotically assisted. The aim of this study was to establish benchmarks for these techniques using two different methods. METHODS: Data from patients undergoing laparoscopically or robotically assisted spleen-preserving distal pancreatectomy were extracted from a multicentre database (2006-2019). Benchmarks for 10 outcomes were calculated using the Achievable Benchmark of Care (ABC) and best-patient-in-best-centre methods. RESULTS: Overall, 951 laparoscopically assisted (77.3 per cent) and 279 robotically assisted (22.7 per cent) procedures were included. Using the ABC method, the benchmarks for laparoscopically assisted and robotically assisted spleen-preserving distal pancreatectomy respectively were: 150 and 207 min for duration of operation, 55 and 100 ml for blood loss, 3.5 and 1.7 per cent for conversion, 0 and 1.7 per cent for failure to preserve the spleen, 27.3 and 34.0 per cent for overall morbidity, 5.1 and 3.3 per cent for major morbidity, 3.6 and 7.1 per cent for pancreatic fistula grade B/C, 5 and 6 days for duration of hospital stay, 2.9 and 5.4 per cent for readmissions, and 0 and 0 per cent for 90-day mortality. Best-patient-in-best-centre methodology revealed milder benchmark cut-offs for laparoscopically and robotically assisted procedures, with operating times of 254 and 262.5 min, blood loss of 150 and 195 ml, conversion rates of 5.8 and 8.2 per cent, rates of failure to salvage spleen of 29.9 and 27.3 per cent, overall morbidity rates of 62.7 and 55.7 per cent, major morbidity rates of 20.4 and 14 per cent, POPF B/C rates of 23.8 and 24.2 per cent, duration of hospital stay of 8 and 8 days, readmission rates of 20 and 15.1 per cent, and 90-day mortality rates of 0 and 0 per cent respectively. CONCLUSION: Two benchmark methods for minimally invasive distal pancreatectomy produced different values, and should be interpreted and applied differently.

Benchmarking of minimally invasive distal pancreatectomy with splenectomy: European multicentre study.

BACKGROUND: Benchmarking is the process to used assess the best achievable results and compare outcomes with that standard. This study aimed to assess best achievable outcomes in minimally invasive distal pancreatectomy with splenectomy (MIDPS). METHODS: This retrospective study included consecutive patients undergoing MIDPS for any indication, between 2003 and 2019, in 31 European centres. Benchmarks of the main clinical outcomes were calculated according to the Achievable Benchmark of Care (ABC™) method. After identifying independent risk factors for severe morbidity and conversion, risk-adjusted ABCs were calculated for each subgroup of patients at risk. RESULTS: A total of 1595 patients were included. The ABC was 2.5 per cent for conversion and 8.4 per cent for severe morbidity. ABC values were 160 min for duration of operation time, 8.3 per cent for POPF, 1.8 per cent for reoperation, and 0 per cent for mortality. Multivariable analysis showed that conversion was associated with male sex (OR 1.48), BMI exceeding 30 kg/m2 (OR 2.42), multivisceral resection (OR 3.04), and laparoscopy (OR 2.24). Increased risk of severe morbidity was associated with ASA fitness grade above II (OR 1.60), multivisceral resection (OR 1.88), and robotic approach (OR 1.87). CONCLUSION: The benchmark values obtained using the ABC method represent optimal outcomes from best achievable care, including low complication rates and zero mortality. These benchmarks should be used to set standards to improve patient outcomes.

Comparison of two radiofrequency-based hemostatic devices: saline-linked bipolar vs. cooled-electrode monopolar.

PURPOSE: To characterize the coagulation zones created by two radiofrequency (RF)-based hemostatic devices: one comprised an internally cooled monopolar electrode and the other comprised externally irrigated bipolar electrodes (saline-linked). MATERIALS AND METHODS: RF-induced coagulation zones were created on ex vivo and in vivo porcine models. Computer modeling was used to determine the RF power distribution in the saline-linked device. RESULTS: Both external (irrigation) and internal cooling effectively prevented tissue sticking. Under ex vivo conditions in 'painting' application mode, coagulation depth increased with the applied power: 2.8 - 5.6 mm with the 3-mm monopolar electrode, 1.6 - 6.0 mm with the 5-mm monopolar electrode and 0.6 - 3.2 mm with the saline-linked bipolar electrodes. Under in vivo conditions and using spot applications, the 3-mm monopolar electrode created coagulation zones of similar depth to the saline-linked bipolar electrodes (around 3 mm), while the 5-mm monopolar electrode created deeper coagulations (4.5 - 6 mm) with less incidence of popping. The presence of saline around the saline-linked bipolar electrodes meant that a significant percentage of RF power (50 - 80%) was dissipated by heating in the saline layer. Coagulation zones were histologically similar for all the tested devices. CONCLUSIONS: Both external (irrigation) and internal cooling in hemostatic RF devices effectively prevent tissue sticking and create similar coagulation zones from a histological point of view. Overall, saline-linked bipolar electrodes tend to create shallower coagulations than those created with an internally cooled monopolar electrode.

Laparoscopic versus open pancreatoduodenectomy: an individual participant data meta-analysis of randomized controlled trials.

BACKGROUND: Randomized trials have compared laparoscopic pancreatoduodenectomy (LPD) to open pancreatoduodenectomy (OPD) with conflicting results. An IPDMA may give more insight into the differences between LPD and OPD, and could identify high-risk subgroups. METHODS: A systematic literature search was performed in the Pubmed, Embase, and the Cochrane library databases (October 2019). Out of 1410 studies, three randomized trials were identified. Primary outcome was major complications (Clavien-Dindo grade ≥ III). Subgroup analyses were performed for high-risk subgroups including patients with BMI of ≥25 kg/m2, pancreatic duct <3 mm, age ≥70 years, and malignancy. RESULTS: Data from 224 patients were collected. After LPD, major complications occurred in 33/114 (29%) patients compared to 34/110 (31%) patients after OPD (adjusted odds ratio (OR) 0.62; 95% confidence interval (CI) 0.3-1.4, P = 0.257). No differences were seen for major complications and 90-day mortality LPD 8 (7%) vs OPD 4 (4%) (adjusted OR 0.2; 95% CI 0.02-1.3, P = 0.080). With LPD, operative time was longer (420 vs 318 min, p < 0.001) and hospital stay was shorter (mean difference -6.97 days). Outcomes remained stable in the high-risk subgroups. CONCLUSION: LPD did not reduce the rate of major postoperative complications as compared to OPD. LPD increased operative time and shortened hospital stay with 7 days.

The Impact of Neoadjuvant Treatment on Survival in Patients Undergoing Pancreatoduodenectomy With Concomitant Portomesenteric Venous Resection: An International Multicenter Analysis.

OBJECTIVE: The aim of this study was to evaluate whether neoadjuvant therapy (NAT) critically influenced microscopically complete resection (R0) rates and long-term outcomes for patients with pancreatic ductal adenocarcinoma who underwent pancreatoduodenectomy (PD) with portomesenteric vein resection (PVR) from a diverse, world-wide group of high-volume centers. SUMMARY OF BACKGROUND DATA: Limited size studies suggest that NAT improves R0 rates and overall survival compared to upfront surgery in R/BR-PDAC patients. METHODS: This multicenter study analyzed consecutive patients with R/BR-PDAC who underwent PD with PVR in 23 high-volume centers from 2009 to 2018. RESULTS: Data from 1192 patients with PD and PVR were collected and analyzed. The median age was 68 [interquartile range (IQR) 60-73] years and 52% were males. Some 186 (15.6%) and 131 (10.9%) patients received neoadjuvant chemotherapy (NAC) alone and neoadjuvant chemoradiotherapy, respectively. The R0/R1/R2 rates were 57%, 39.3%, and 3.2% in patients who received NAT compared to 46.6%, 49.9%, and 3.5% in patients who did not, respectively (P =0.004). The 1-, 3-, and 5-year OS in patients receiving NAT was 79%, 41%, and 29%, while for those that did not it was 73%, 29%, and 18%, respectively (P <0.001). Multivariable analysis showed no administration of NAT, high tumor grade, lymphovascular invasion, R1/R2 resection, no adjuvant chemotherapy, occurrence of Clavien-Dindo grade 3 or higher postoperative complications within 90 days, preoperative diabetes mellitus, male sex and portal vein involvement were negative independent predictive factors for OS. CONCLUSION: Patients with PDAC of the pancreatic head expected to undergo venous reconstruction should routinely be considered for NAT.

Short pulsed microwave ablation: computer modeling and ex vivo experiments.

PURPOSE: To study the differences between continuous and short-pulse mode microwave ablation (MWA). METHODS: We built a computational model for MWA including a 200 mm long and 14 G antenna from Amica-Gen and solved an electromagnetic-thermal coupled problem using COMSOL Multiphysics. We compared the coagulation zone (CZ) sizes created with pulsed and continuous modes under ex vivo and in vivo conditions. The model was used to compare long vs. short pulses, and 1000 W high-powered short pulses. Ex vivo experiments were conducted to validate the model. RESULTS: The computational models predicted the axial diameter of the CZ with an error of 2-3% and overestimated the transverse diameter by 9-11%. For short pulses, the ex vivo computer modeling results showed a trend toward larger CZ when duty cycles decreases. In general, short pulsed mode yielded higher CZ diameters and volumes than continuous mode, but the differences were not significant (<5%), as in terms of CZ sphericity. The same trends were observed in the simulations mimicking in vivo conditions. Both CZ diameter and sphericity were similar with short and long pulses. Short 1000 W pulses produced smaller sphericity and similar CZ sizes under in vivo and ex vivo conditions. CONCLUSIONS: The characteristics of the CZ created by continuous and pulsed MWA show no significant differences from ex vivo experiments and computer simulations. The proposed idea of enlarging coagulation zones and improving their sphericity in pulsed mode was not evident in this study.

Clinical case report: endoluminal thermal ablation of main pancreatic duct for patients at high risk of postoperative pancreatic fistula after pancreaticoduodenectomy.

PURPOSE: Multiple attempts have been made to manage the pancreatic stump and the pancreatic duct in order to reduce the rate of postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD), however radiofrequency-based technologies could help to achieve this goal. Previous encouraging clinical and experimental results support the use of endoluminal thermal ablation (ETHA) of the main pancreatic duct to reduce pancreatic exocrine secretion and hence POPF. We here describe our initial clinical experience with ETHA of the main pancreatic duct in two cases at high risk of POPF. METHODS: Two cases underwent PD for malignancy with a high risk of POPF (adenocarcinoma, obese patients, surgical difficulties with heavy intraoperative blood loss, soft pancreas or walled-off pancreatitis and a tight small pancreatic main duct). In both cases, ETHA of the main pancreatic duct was conducted intraoperatively just before Blumgart-type pancreatic-jejunal anastomosis using a ClosureFast catheter (Medtronic, Mansfield, MA, USA) normally used for varicose vein treatment (therefore an off-label use). RESULTS: Although a clear radiological POPF was detected in the second case, the clinical postoperative course in both cases was uneventful. Little pancreatic fluid collected in the abdominal drainage with low levels of amylase enzyme, confirming low exocrine pancreatic function. No other procedure-related complications were detected. CONCLUSION: Endoluminal thermal ablation of the main pancreatic duct may be a feasible and safe technique to reduce the adverse effects of POPF after PD.

Defining Benchmark Outcomes for Pancreatoduodenectomy With Portomesenteric Venous Resection.

OBJECTIVE: The aim of this study was to establish clinically relevant outcome benchmark values using criteria for pancreatoduodenectomy (PD) with portomesenteric venous resection (PVR) from a low-risk cohort managed in high-volume centers. SUMMARY BACKGROUND DATA: PD with PVR is regarded as the standard of care in patients with cancer involvement of the portomesenteric venous axis. There are, however, no benchmark outcome indicators for this population which hampers comparisons of patients undergoing PD with and without PVR resection. METHODS: This multicenter study analyzed patients undergoing PD with any type of PVR in 23 high-volume centers from 2009 to 2018. Nineteen outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of the centers (NCT04053998). RESULTS: Out of 1462 patients with PD and PVR, 840 (58%) formed the benchmark cohort, with a mean age was 64 (SD11) years, 413 (49%) were females. Benchmark cutoffs, among others, were calculated as follows: Clinically relevant pancreatic fistula rate (International Study Group of Pancreatic Surgery): ≤14%; in-hospital mortality rate: ≤4%; major complication rate Grade≥3 and the CCI up to 6 months postoperatively: ≤36% and ≤26, respectively; portal vein thrombosis rate: ≤14% and 5-year survival for patients with pancreatic ductal adenocarcinoma: ≥9%. CONCLUSION: These novel benchmark cutoffs targeting surgical performance, morbidity, mortality, and oncological parameters show relatively inferior results in patients undergoing vascular resection because of involvement of the portomesenteric venous axis. These benchmark values however can be used to conclusively assess the results of different centers or surgeons operating on this high-risk group.

How large is the periablational zone after radiofrequency and microwave ablation? Computer-based comparative study of two currently used clinical devices.

PURPOSE: To compare the size of the coagulation (CZ) and periablational (PZ) zones created with two commercially available devices in clinical use for radiofrequency (RFA) and microwave ablation (MWA), respectively. METHODS: Computer models were used to simulate RFA with a 3-cm Cool-tip applicator and MWA with an Amica-Gen applicator. The Arrhenius model was used to compute the damage index (Ω). CZ was considered when Ω > 4.6 (>99% of damaged cells). Regions with 0.6<Ω < 2.1 were considered as the PZ (tissue that has undergone moderate sub-ablative hyperthermia). The ratio of PZ volume to CZ volume (PZ/CZ) was regarded as a measure of performance, since a low value implies achieving a large CZ while keeping the PZ small. RESULTS: Ten-min RFA (51 W) created smaller periablational zones than 10-min MWA (11.3 cm3 vs. 17.2-22.9 cm3, for 60-100 W MWA, respectively). Prolonging duration from 5 to 10 min increased the PZ in MWA more than in RFA (2.7 cm3 for RFA vs. 8.3-11.9 cm3 for 60-100 W MWA, respectively). PZ/CZ for RFA were relatively high (65-69%), regardless of ablation time, while those for MWA were highly dependent on the duration (increase of up to 25% between 5 and 10 min) and on the applied power (smaller values as power was raised, 102% for 60 W vs. 81% for 100 W, both for 10 min). The lowest PZ/CZ across all settings was 56%, obtained with 100 W-5 min MWA. CONCLUSIONS: Although RFA creates smaller periablational zones than MWA, 100 W-5 min MWA provides the lowest PZ/CZ.

Development of a catheter-based technique for endoluminal radiofrequency sealing of pancreatic duct.

Introduction: Endoluminal sealing of the pancreatic duct by glue or sutures facilitates the management of the pancreatic stump. Our objective was to develop a catheter-based alternative for endoluminal radiofrequency (RF) sealing of the pancreatic duct. Materials and methods: We devised a novel RF ablation technique based on impedance-guided catheter pullback. First, bench tests were performed on ex vivo models to tune up the technique before the in vivo study, after which endoluminal RF sealing of a ∼10 cm non-transected pancreatic duct was conducted on porcine models using a 3 Fr catheter. After 30 days, sealing effectiveness was assessed by a permeability test and a histological analysis. Results: The RF technique was feasible in all cases and delivered ∼5 W of power on an initial impedance of 308 ± 60 Ω. Electrical impedance evolution was similar in all cases and provided guidance for modulating the pullback speed to avoid tissue sticking and achieve a continuous lesion. During the follow-up the animals rate of weight gain was significantly reduced (p < 0.05). Apart from signs of exocrine atrophy, no other postoperative complications were found. At necropsy, the permeability test failed and the catheter could not be reintroduced endoluminally, confirming that sealing had been successful. The histological analysis revealed a homogeneous exocrine atrophy along the ablated segment in all the animals. Conclusions: Catheter-based RF ablation could be used effectively and safely for endoluminal sealing of the pancreatic duct. The findings suggest that a fully continuous lesion may not be required to obtain complete exocrine atrophy.