The Value of Textbook Outcome in Benchmarking Pancreatoduodenectomy for Nonfunctioning Pancreatic Neuroendocrine Tumors.

BACKGROUND: Textbook outcome (TO) is a composite variable that can define the quality of pancreatic surgery. The aim of this study is to evaluate TO after pancreatoduodenectomy (PD) for nonfunctioning pancreatic neuroendocrine tumors (NF-PanNETs). PATIENTS AND METHODS: All patients who underwent PD for NF-PanNETs (2007-2016) in different centers were included in this retrospective study. TO was defined as the absence of severe postoperative complications and mortality, length of hospital stay ≤ 19 days, R0 resection, and at least 12 lymph nodes harvested. RESULTS: Overall, 477 patients were included. The TO rate was 32%. Tumor size [odds ratio (OR) 1.696; p = 0.013], a minimally invasive approach (OR 12.896; p = 0.001), and surgical volume (OR 2.062; p = 0.023) were independent predictors of TO. The annual frequency of PDs increased over time as well as the overall rate of TO. At a median follow-up of 44 months, patients who achieved TO had similar disease-free (p = 0.487) and overall survival (p = 0.433) rates compared with patients who did not achieve TO. TO rate in patients with NF-PanNET > 2 cm was 35% versus 27% in patients with NF-PanNET ≤ 2 cm (p = 0.044). Considering only NF-PanNETs > 2 cm, patients with TO and those without TO had comparable 5-year overall survival rates (p = 0.766) CONCLUSIONS: TO is achieved in one-third of patients after PD for NF-PanNETs and is not associated with a benefit in terms of long-term survival.

Efficacy and Toxicity Analysis of mFOLFIRINOX in High-Grade Gastroenteropancreatic Neuroendocrine Neoplasms.

BACKGROUND: High-grade neuroendocrine neoplasms (NENs) comprise both well-differentiated grade 3 neuroendocrine tumors (G3 NETs) and poorly differentiated neuroendocrine carcinomas (NECs). Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) nearly always include poorly differentiated NEC as the neuroendocrine component. The efficacy and safety of frontline mFOLFIRINOX chemotherapy has never been investigated in patients with high-grade NENs. PATIENTS AND METHODS: We conducted a multi-institutional retrospective analysis of patients with advanced high-grade NEN of the gastroenteropancreatic tract or of unknown origin seen between February 2016 and April 2023 who received treatment with frontline mFOLFIRINOX. RESULTS: A total of 35 patients were included (G3 NETs: n=2; NECs: n=25; MiNENs: n=8; stage III: n=5; stage IV: n=30). The objective response rate was 77% (complete response: 3%; partial response: 74%). Median progression-free survival was 12 months (95% CI, 9.2-16.2 months) and median overall survival was 20.6 months (95% CI, 17.2-30.6 months). No significant differences in efficacy were seen according to primary site, histopathology, and Ki-67 proliferative index. All 5 patients with stage III disease who received mFOLFIRINOX obtained an objective response and underwent radical surgery or definitive radiotherapy with curative intent, with a recurrence rate of 40%. Grade 3 or 4 adverse events were observed in 43% of patients (mainly neutropenia and diarrhea). Females were at significantly increased risk of developing severe toxicities. CONCLUSIONS: mFOLFIRINOX shows antitumor activity against high-grade NENs. Well-designed, prospective clinical trials are needed to assess the efficacy of mFOLFIRINOX in both the neoadjuvant and metastatic settings.

Safety and performance of a synthetic sealant patch aimed to prevent postoperative pancreatic fistula after distal pancreatectomy (SHIELDS) - Prospective international multicenter phase II study.

OBJECTIVE: The incidence for clinically relevant postoperative pancreatic fistulas (CR-POPF) in distal pancreatectomy (DP) ranges up to 25%. None of the available sealants significantly reduce CR-POPF. A new biodegradable sealant patch was able to reduce POPF and to achieve bleeding control in a preclinical porcine DP model. The aim of this first-in-human study was to assess the safety and performance of the sealant patch. METHODS: In this multicenter, single-arm study, 40 patients undergoing distal pancreatectomy were prospectively enrolled from 8 centers. Following surgical resection, the transection plane was closed according to the standard of care and manually covered with the sealant patch. As primary endpoint the incidence of CR-POPF up to 30-days postoperatively was evaluated. The secondary endpoints included the assessment of complications and device usability. RESULTS: Among 40 patients after distal pancreatectomy, CR-POPF occurred in 7 (17.5%) up to postoperative day 30. No type C POPF was observed. There was no intraoperative bleeding observed after patch application. CONCLUSION: The results of this international phase II study demonstrate promising results of a new sealant patch regarding the rate of CR-POPF. Randomized studies are now needed to confirm the superiority of the current patch as compared to the best current practice.

Pancreatic Enucleation Patients Share the Same Quality of Life as the General Population at Long-Term Follow-Up: A Propensity Score-Matched Analysis.

OBJECTIVE: The aim of this study was to assess short- and long-term outcomes including quality of life (QoL) following pancreatic enucleation (PE). BACKGROUND: PE is deemed to preserve both the endocrine and the exocrine function while ensuring radicality. However, to assess whether this reflects an actual benefit perceived by patients, QoL has to be considered. METHODS: Data from all consecutive patients undergoing PE from January 2010 to December 2019 were retrospectively analyzed. Surgical outcomes were graded according to the Clavien-Dindo classification, and EORTC-C30 and the EORTC-Pan26 were administered as a cross-sectional assessment of QoL. A control group consisting of healthy individuals from the general population was obtained and matched using the propensity score matching method. RESULTS: Eighty-one patients underwent PE using the open (59.3%), laparoscopic (27.2%), or robot-assisted (13.5%) approach. Sixty-five (80.2%) patients exhibited functioning/nonfunctioning pancreatic neuroendocrine tumors at final pathology.Surgical morbidity and complications of a Clavien-Dindo grade ≥3 were 48.1% and 16.0%, respectively. In-hospital mortality was 0%. Postoperative pancreatic fistula, post-pancreatectomy hemorrhage, and delayed gastric emptying rates were 21.0%, 9.9%, and 4.9%, respectively.Patients returned the questionnaires after a median of 74.2 months from the index surgery. Postoperative new onset of diabetes mellitus (NODM) was observed in 5 subjects (7.1%), with age being an independent predictor. Seven patients (10.0%) developed postoperative exocrine insufficiency. At the analysis of QoL, all function and symptom scales were comparable between the 2 groups, except for 2 of the EORTC-Pan 26 symptom scales, ("worries for the future" and "body image", P < 0.05). CONCLUSIONS: Despite being associated with significant postoperative morbidity, PE provides excellent long-term outcomes. The risk of NODM is low and related to patient age, with QoL being comparable to the general population. Such information should drive surgeons to pursue PE whenever properly indicated.

Distal Pancreatectomy Fistula Risk Score (D-FRS): Development and International Validation.

OBJECTIVE: To develop 2 distinct preoperative and intraoperative risk scores to predict postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP) to improve preventive and mitigation strategies, respectively. BACKGROUND: POPF remains the most common complication after DP. Despite several known risk factors, an adequate risk model has not been developed yet. METHODS: Two prediction risk scores were designed using data of patients undergoing DP in 2 Italian centers (2014-2016) utilizing multivariable logistic regression. The preoperative score (calculated before surgery) aims to facilitate preventive strategies and the intraoperative score (calculated at the end of surgery) aims to facilitate mitigation strategies. Internal validation was achieved using bootstrapping. These data were pooled with data from 5 centers from the United States and the Netherlands (2007-2016) to assess discrimination and calibration in an internal-external validation procedure. RESULTS: Overall, 1336 patients after DP were included, of whom 291 (22%) developed POPF. The preoperative distal fistula risk score (preoperative D-FRS) included 2 variables: pancreatic neck thickness [odds ratio: 1.14; 95% confidence interval (CI): 1.11-1.17 per mm increase] and pancreatic duct diameter (OR: 1.46; 95% CI: 1.32-1.65 per mm increase). The model performed well with an area under the receiver operating characteristic curve of 0.83 (95% CI: 0.78-0.88) and 0.73 (95% CI: 0.70-0.76) upon internal-external validation. Three risk groups were identified: low risk (<10%), intermediate risk (10%-25%), and high risk (>25%) for POPF with 238 (18%), 684 (51%), and 414 (31%) patients, respectively. The intraoperative risk score (intraoperative D-FRS) added body mass index, pancreatic texture, and operative time as variables with an area under the receiver operating characteristic curve of 0.80 (95% CI: 0.74-0.85). CONCLUSIONS: The preoperative and the intraoperative D-FRS are the first validated risk scores for POPF after DP and are readily available at: http://www.pancreascalculator.com . The 3 distinct risk groups allow for personalized treatment and benchmarking.

Endoscopic Ultrasound-guided Radiofrequency Ablation Versus Surgical Resection for Treatment of Pancreatic Insulinoma.

BACKGROUND & AIMS: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is emerging as a safe and effective treatment for pancreatic neuroendocrine tumors. We aimed to compare EUS-RFA and surgical resection for the treatment of pancreatic insulinoma (PI). METHODS: Patients with sporadic PI who underwent EUS-RFA at 23 centers or surgical resection at 8 high-volume pancreatic surgery institutions between 2014 and 2022 were retrospectively identified and outcomes compared using a propensity-matching analysis. Primary outcome was safety. Secondary outcomes were clinical efficacy, hospital stay, and recurrence rate after EUS-RFA. RESULTS: Using propensity score matching, 89 patients were allocated in each group (1:1), and were evenly distributed in terms of age, sex, Charlson comorbidity index, American Society of Anesthesiologists score, body mass index, distance between lesion and main pancreatic duct, lesion site, size, and grade. Adverse event (AE) rate was 18.0% and 61.8% after EUS-RFA and surgery, respectively (P < .001). No severe AEs were observed in the EUS-RFA group compared with 15.7% after surgery (P < .0001). Clinical efficacy was 100% after surgery and 95.5% after EUS-RFA (P = .160). However, the mean duration of follow-up time was shorter in the EUS-RFA group (median, 23 months; interquartile range, 14-31 months vs 37 months; interquartile range, 17.5-67 months in the surgical group; P < .0001). Hospital stay was significantly longer in the surgical group (11.1 ± 9.7 vs 3.0 ± 2.5 days in the EUS-RFA group; P < .0001). Fifteen lesions (16.9%) recurred after EUS-RFA and underwent a successful repeat EUS-RFA (11 patients) or surgical resection (4 patients). CONCLUSION: EUS-RFA is safer than surgery and highly effective for the treatment of PI. If confirmed in a randomized study, EUS-RFA treatment can become first-line therapy for sporadic PI.

Endoscopic ultrasound fine-needle biopsy to assess DAXX/ATRX expression and alternative lengthening of telomeres status in non-functional pancreatic neuroendocrine tumors.

BACKGROUND/OBJECTIVES: Death domain-associated protein (DAXX) and/or α-thalassemia/mental retardation X-linked (ATRX) chromatin remodeling genes mutations and alternative lengthening of telomeres (ALT) activation are associated with more aggressive behavior of non-functional pancreatic neuroendocrine tumors (NF-PanNETs). We aimed to evaluate the reliability of such markers on endoscopic-ultrasound fine-needle biopsy (EUS-FNB) specimens. METHODS: Patients who underwent EUS-FNB and subsequent surgical resection for PanNETs between January 2017 and December 2019 were retrospectively identified. Immunohistochemistry (IHC) to evaluate DAXX/ATRX expression and fluorescence in situ hybridization (FISH) for ALT status were performed. Primary outcome was the concordance rate of markers expression between EUS-FNB and surgical specimens. Secondary aims were association between markers and lesion aggressiveness, their diagnostic performance in predicting aggressiveness, and agreement of preoperative and post-surgical Ki67-based grading. RESULTS: Forty-one NF-PanNETs (mean diameter 36.1 ± 26.5 mm) were included. Twenty-four showed features of lesion aggressiveness. Concordance of expressions of DAXX, ATRX, and ALT status between EUS-FNB and surgical specimens were 95.1% (κ = 0.828; p < 0.001), 92.7% (κ = 0.626; p < 0.001), and 100% (κ = 1; p < 0.001), respectively. DAXX/ATRX loss and ALT-positivity were significantly (p < 0.05) associated with metastatic lymphnodes and lymphovascular invasion. The combination of all tumor markers (DAXX/ATRX loss + ALT-positivity + grade 2) reached an accuracy of 73.2% (95%CI 57.1-85.8) in identifying aggressive lesions. Pre- and post-operative ki-67-based grading was concordant in 80.5% of cases (k = 0.573; p < 0.001). CONCLUSION: DAXX/ATRX expression and ALT status can be accurately evaluated in a preoperative setting on EUS-FNB samples, potentially improving the identification of patients with increased risk and poorer prognosis.

Whole-genome landscape of pancreatic neuroendocrine tumours.

The diagnosis of pancreatic neuroendocrine tumours (PanNETs) is increasing owing to more sensitive detection methods, and this increase is creating challenges for clinical management. We performed whole-genome sequencing of 102 primary PanNETs and defined the genomic events that characterize their pathogenesis. Here we describe the mutational signatures they harbour, including a deficiency in G:C > T:A base excision repair due to inactivation of MUTYH, which encodes a DNA glycosylase. Clinically sporadic PanNETs contain a larger-than-expected proportion of germline mutations, including previously unreported mutations in the DNA repair genes MUTYH, CHEK2 and BRCA2. Together with mutations in MEN1 and VHL, these mutations occur in 17% of patients. Somatic mutations, including point mutations and gene fusions, were commonly found in genes involved in four main pathways: chromatin remodelling, DNA damage repair, activation of mTOR signalling (including previously undescribed EWSR1 gene fusions), and telomere maintenance. In addition, our gene expression analyses identified a subgroup of tumours associated with hypoxia and HIF signalling.

Corrigendum: Whole-genome landscape of pancreatic neuroendocrine tumours.

This corrects the article DOI: 10.1038/nature21063.

Non-functional pancreatic neuroendocrine tumours: ATRX/DAXX and alternative lengthening of telomeres (ALT) are prognostically independent from ARX/PDX1 expression and tumour size.

OBJECTIVE: Recent studies have found aristaless-related homeobox gene (ARX)/pancreatic and duodenal homeobox 1 (PDX1), alpha-thalassemia/mental retardation X-linked (ATRX)/death domain-associated protein (DAXX) and alternative lengthening of telomeres (ALT) to be promising prognostic biomarkers for non-functional pancreatic neuroendocrine tumours (NF-PanNETs). However, they have not been comprehensively evaluated, especially among small NF-PanNETs (≤2.0 cm). Moreover, their status in neuroendocrine tumours (NETs) from other sites remains unknown. DESIGN: An international cohort of 1322 NETs was evaluated by immunolabelling for ARX/PDX1 and ATRX/DAXX, and telomere-specific fluorescence in situ hybridisation for ALT. This cohort included 561 primary NF-PanNETs, 107 NF-PanNET metastases and 654 primary, non-pancreatic non-functional NETs and NET metastases. The results were correlated with numerous clinicopathological features including relapse-free survival (RFS). RESULTS: ATRX/DAXX loss and ALT were associated with several adverse prognostic findings and distant metastasis/recurrence (p<0.001). The 5-year RFS rates for patients with ATRX/DAXX-negative and ALT-positive NF-PanNETs were 40% and 42% as compared with 85% and 86% for wild-type NF-PanNETs (p<0.001 and p<0.001). Shorter 5-year RFS rates for ≤2.0 cm NF-PanNETs patients were also seen with ATRX/DAXX loss (65% vs 92%, p=0.003) and ALT (60% vs 93%, p<0.001). By multivariate analysis, ATRX/DAXX and ALT status were independent prognostic factors for RFS. Conversely, classifying NF-PanNETs by ARX/PDX1 expression did not independently correlate with RFS. Except for 4% of pulmonary carcinoids, ATRX/DAXX loss and ALT were only identified in primary (25% and 29%) and NF-PanNET metastases (62% and 71%). CONCLUSIONS: ATRX/DAXX and ALT should be considered in the prognostic evaluation of NF-PanNETs including ≤2.0 cm tumours, and are highly specific for pancreatic origin among NET metastases of unknown primary.

Pancreatoduodenectomy at the Verona Pancreas Institute: the Evolution of Indications, Surgical Techniques, and Outcomes: A Retrospective Analysis of 3000 Consecutive Cases.

OBJECTIVE: The aim of the present study was to critically reappraise the experience at our high-volume institution to obtain new insights for future directions. SUMMARY BACKGROUND DATA: The indications, surgical techniques, and perioperative management of pancreatoduodenectomy (PD) have profoundly evolved over the last 20 years. METHODS: All consecutive PDs performed during the last 20 years at the Verona Pancreas Institute were divided into four 5-year timeframes and retrospectively analyzed in terms of indications, intraoperative features, and surgical outcomes. Significant milestones were provided to understand practice changes using a before-after analysis method. RESULTS: The study population consisted of 3000 patients. The median age, ASA ≥ 3 and number of nonbenchmark cases significantly increased over time ( P < 0.005). Pancreatic cancer was the leading indication, representing 60% of patients/year in the last timeframe, 40% of whom received neoadjuvant treatment. Conversely, after the development of International Guidelines, the proportion of resected cystic neoplasms progressively and thoroughly decreased. Given the increased complexity of surgery for pancreatic cancer, the evolution of technologies, surgical techniques, and postoperative management allowed the maintenance of favorable surgical outcomes over time, with a stable 20.0% of patients with a Clavien-Dindo grade ≥ 3, an 11.7% failure to rescue and a 2.3% in-hospital mortality rate. The incidence of postoperative pancreatic fistula, hemorrhage, and delayed gastric emptying was 22.4%, 13.4%, and 12.4%, respectively. CONCLUSIONS: PD significantly evolved in Verona over the past 2 decades. Surgeries of greater complexity are currently performed on increasingly frailer patients, mostly for pancreatic cancer and often after neoadjuvant chemotherapy. However, the progression of all fields of pancreatic surgery, including the expanding use of postoperative pancreatic fistula mitigation strategies, has allowed satisfactory outcomes to be maintained.

Ki-67 assessment of pancreatic neuroendocrine neoplasms: Systematic review and meta-analysis of manual vs. digital pathology scoring.

Ki-67 assessment is a key step in the diagnosis of neuroendocrine neoplasms (NENs) from all anatomic locations. Several challenges exist related to quantifying the Ki-67 proliferation index due to lack of method standardization and inter-reader variability. The application of digital pathology coupled with machine learning has been shown to be highly accurate and reproducible for the evaluation of Ki-67 in NENs. We systematically reviewed all published studies on the subject of Ki-67 assessment in pancreatic NENs (PanNENs) employing digital image analysis (DIA). The most common advantages of DIA were improvement in the standardization and reliability of Ki-67 evaluation, as well as its speed and practicality, compared to the current gold standard approach of manual counts from captured images, which is cumbersome and time consuming. The main limitations were attributed to higher costs, lack of widespread availability (as of yet), operator qualification and training issues (if it is not done by pathologists), and most importantly, the drawback of image algorithms counting contaminating non-neoplastic cells and other signals like hemosiderin. However, solutions are rapidly developing for all of these challenging issues. A comparative meta-analysis for DIA versus manual counting shows very high concordance (global coefficient of concordance: 0.94, 95% CI: 0.83-0.98) between these two modalities. These findings support the widespread adoption of validated DIA methods for Ki-67 assessment in PanNENs, provided that measures are in place to ensure counting of only tumor cells either by software modifications or education of non-pathologist operators, as well as selection of standard regions of interest for analysis. NENs, being cellular and monotonous neoplasms, are naturally more amenable to Ki-67 assessment. However, lessons of this review may be applicable to other neoplasms where proliferation activity has become an integral part of theranostic evaluation including breast, brain, and hematolymphoid neoplasms.

Survival after active surveillance versus upfront surgery for incidental small pancreatic neuroendocrine tumours.

BACKGROUND: The safety of observing small non-functioning pancreatic neuroendocrine tumours (NF-Pan-NETs) remains under debate. METHODS: This was a multicentre retrospective study of patients with small incidental NF-Pan-NETs. Survival of patients who underwent upfront surgery versus active surveillance was compared. The risk of death was matched with that in the healthy population. The excess hazard rate and probability of a normal lifespan (NLP) were calculated. Propensity score matching (PSM) with a 1 : 1 ratio was used to minimize the risk of selection bias. RESULTS: Some 222 patients (43.7 per cent) underwent upfront surgery and 285 (56.3 per cent) were observed. The excess hazard rate for the entire cohort was quantifiable as 0.04 (95 per cent c.i. 0 to 0.08) deaths per 1000 persons per year, and the NLP was 99.7 per cent. Patients in the active surveillance group were older (median age 65 versus 58 years; P < 0.001), and more often had co-morbidity (45.3 versus 24.8 per cent; P = 0.001), and smaller tumours (median 12 versus 13 mm; P < 0.001), less frequently located in the pancreatic body-tail (59.5 versus 69.6 per cent; P = 0.008, 59.3 versus 73.9 per cent; P = 0.001). Median follow-up was longer for patients who underwent upfront surgery (5.6 versus 2.7 years; P < 0.001). After PSM, 118 patients per group were included. The excess hazard rates were 0.2 and 0.9 deaths per 1000 persons per year (P = 0.020) for patients in the active surveillance and upfront surgery groups respectively. Corresponding NLPs were 99.9 and 99.5 per cent respectively (P = 0.011). CONCLUSION: Active surveillance of small incidental NF-Pan-NETs is a reasonable alternative to resection.

Dual-Tracer (68Ga-DOTATOC and 18F-FDG-)-PET/CT Scan and G1-G2 Nonfunctioning Pancreatic Neuroendocrine Tumors: A Single-Center Retrospective Evaluation of 124 Nonmetastatic Resected Cases.

INTRODUCTION: The combined use of 68gallium (68Ga)-DOTA-peptides and 18fluorine-fluoro-2-deoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) scans in the workup of pancreatic neuroendocrine tumors (PanNETs) is controversial. This study aimed at assessing both tracers' capability to identify tumors and to assess its association with pathological predictors of recurrence. METHODS: Prospectively collected, preoperative, dual-tracer PET/CT scan data of G1-G2, nonmetastatic, PanNETs that underwent surgery between January 2013 and October 2019 were retrospectively analyzed. RESULTS: The final cohort consisted of 124 cases. There was an approximately equal distribution of males and females (50.8%/49.2%) and G1 and G2 tumors (49.2%/50.8%). The disease was detected in 122 (98.4%) and 64 (51.6%) cases by 68Ga-DOTATOC and by 18F-FDG PET/CT scans, respectively, with a combined sensitivity of 99.2%. 18F-FDG-positive examinations found G2 tumors more often than G1 (59.4 vs. 40.6%; p = 0.036), and 18F-FDG-positive PanNETs were larger than negative ones (median tumor size 32 mm, interquartile range [IQR] 21 vs. 26 mm, IQR 20; p = 0.019). The median Ki67 for 18F-FDG-positive and -negative examinations was 3 (IQR 4) and 2 (IQR 4), respectively (p = 0.029). At least 1 pathological predictor of recurrence was present in 74.6% of 18F-FDG-positive cases (vs. 56.7%; p = 0.039), whereas this was not found when dichotomizing the PanNETs by their dimensions (≤/>20 mm). None of the 2 tracers predicted nodal metastasis. The receiver operating characteristic curve analysis showed that 18F-FDG uptake higher than 4.2 had a sensitivity of 49.2% and specificity of 73.3% for differentiating G1 from G2 (AUC = 0.624, p = 0.009). CONCLUSION: The complementary adoption of 68Ga-DOTATOC and 18F-FDG tracers may be valuable in the diagnostic workup of PanNETs despite not being a game-changer for the management of PanNETs ≤20 mm.

401 consecutive minimally invasive distal pancreatectomies: lessons learned from 20 years of experience.

BACKGROUND: This study aimed to discuss and report the trend, outcomes, and learning curve effect after minimally invasive distal pancreatectomy (MIDP) at two high-volume centres. METHODS: Patients undergoing MIDP between January 1999 and December 2018 were retrospectively identified from prospectively maintained electronic databases. The entire cohort was divided into two groups constituting the "early" and "recent" phases. The learning curve effect was analyzed for laparoscopic (LDP) and robotic distal pancreatectomy (RDP). The follow-up was at least 2 years. RESULTS: The study population included 401 consecutive patients (LDP n = 300, RDP n = 101). Twelve surgeons performed MIDP during the study period. Although patients were more carefully selected in the early phase, in terms of median age (49 vs. 55 years, p = 0.026), ASA class higher than 2 (3% vs. 9%, p = 0.018), previous abdominal surgery (10% vs. 34%, p < 0.001), and pancreatic adenocarcinoma (PDAC) (7% vs. 15%, p = 0.017), the recent phase had similar perioperative outcomes. The increase of experience in LDP was inversely associated with the operative time (240 vs 210 min, p < 0.001), morbidity rate (56.5% vs. 40.1%, p = 0.005), intra-abdominal collection (28.3% vs. 17.3%, p = 0.023), and length of stay (8 vs. 7 days, p = 0.009). Median survival in the PDAC subgroup was 53 months. CONCLUSION: In the setting of high-volume centres, the surgical training of MIDP is associated with acceptable rates of morbidity. The learning curve can be largely achieved by several team members, improving outcomes over time. Whenever possible resection of PDAC guarantees adequate oncological results and survival.

A randomized controlled trial of stapled versus ultrasonic transection in distal pancreatectomy.

BACKGROUND: The pancreatic transection method during distal pancreatectomy is thought to influence postoperative fistula rates. Yet, the optimal technique for minimizing fistula occurrence is still unclear. The present randomized controlled trial compared stapled versus ultrasonic transection in elective distal pancreatectomy. METHODS: Patients undergoing distal pancreatectomy from July 2018 to July 2020 at two high-volume institutions were considered for inclusion. Exclusion criteria were contiguous organ resection and a parenchymal thickness > 17 mm on intraoperative ultrasound. Eligible patients were randomized in a 1:1 ratio to stapled transection (Endo GIA Reinforced Reload with Tri-Staple Technology®) or ultrasonic transection (Harmonic Focus® + or Harmonic Ace® + shears). The primary endpoint was postoperative pancreatic fistula. Secondary endpoints included overall complications, abdominal collections, and length of hospital stay. RESULTS: Overall, 72 patients were randomized in the stapled transection arm and 73 patients in the ultrasonic transection arm. Postoperative pancreatic fistula occurred in 23 patients (16%), with a comparable incidence between groups (12% in stapled transection versus 19% in ultrasonic dissection arm, p = 0.191). Overall complications did not differ substantially (35% in stapled transection versus 44% in ultrasonic transection arm, p = 0.170). There was an increased incidence of abdominal collections in the ultrasonic dissection group (32% versus 14%, p = 0.009), yet the need for percutaneous drain did not differ between randomization arms (p = 0.169). The median length of stay was 8 days in both groups (p = 0.880). Intraoperative blood transfusion was the only factor independently associated with postoperative pancreatic fistula on logistic regression analysis (OR 4.8, 95% CI 1.2-20.0, p = 0.032). CONCLUSION: The present randomized controlled trial of stapled versus ultrasonic transection in elective distal pancreatectomy demonstrated no significant difference in postoperative pancreatic fistula rates and no substantial clinical impact on other secondary endpoints.

Modified Frailty Index to Assess Risk in Elderly Patients Undergoing Distal Pancreatectomy: A Retrospective Single-Center Study.

BACKGROUND: To compare the postoperative course of elderly patients (≥70 years) submitted to minimally invasive (MIDP) versus open distal pancreatectomy (ODP) and to evaluate if the modified Frailty Index (mFI) predicts the surgical course of elderly patients submitted to DP. METHODS: Data of patients aged ≥70 who underwent DP at a single institution between March 2011 and December 2019 were retrospectively retrieved. A 2:1 propensity score matching (PSM) was used to correct for differences in baseline characteristics. Then, postoperative complications were compared between the two groups (MIDP vs. ODP). Additionally, the entire cohort of DP elderly patients was stratified according to the mFI into three groups: non-frail (mFI = 0), mildly frail (mFI = 1/2), or severely frail (mFI = 3) and then compared. RESULTS: A total of 204 patients were analyzed. After PSM, 40 MIDP and 80 ODP patients were identified. The complications considered stratified homogenously between the two groups, with no statistically significant differences. The severity of the postoperative course increased as mFI did among the three groups regarding any complication (p = 0.022), abdominal collection (p = 0.014), pulmonary complication (p = 0.001), postoperative confusion (p = 0.047), Clavien-Dindo severity ≥3 events (p = 0.036), and length of stay (p = 0.018). CONCLUSIONS: Elderly patients can be safely submitted to MIDP. The mFI identifies frail elderly patients more prone to develop surgical and non-surgical complications after DP.

Hemodynamics and remodeling of the portal confluence in patients with malignancies of the pancreatic head: a pilot study towards planned and circumferential vein resections.

BACKGROUND: We designed a retrospective computational study to evaluate the effects of hemodynamics on portal confluence remodeling in real models of patients with malignancies of the pancreatic head. METHODS: Patient-specific models were created according to computed tomography data. Fluid dynamics was simulated by using finite-element methods. Computational results were compared to morphological findings. RESULTS: Five patients underwent total pancreatectomy, one had duodenopancreatectomy. Vein resection was performed en-bloc with the specimen. Histopathological findings showed that in patients without a vein stenosis and a normal hemodynamics, the three-layered wall of the vein was preserved. In patients with a stenosis > 70% of vein diameter and modified hemodynamics, the three-layered structure of the resected vein was replaced by a dense inflammatory infiltrate in absence of tumor infiltration. CONCLUSIONS: The portal confluence involved by malignancies of the pancreatic head undergoes a remodeling that is not mainly due to a wall infiltration by the tumor but instead to a persistent pathological hemodynamics that disrupts the balance between eutrophic remodeling and degradative process of the vein wall that can lead to the complete upheaval of the three-layered vein wall. This finding can have useful surgical application in planning resection of the vein involved by tumor growth.

Immune landscape, evolution, hypoxia-mediated viral mimicry pathways and therapeutic potential in molecular subtypes of pancreatic neuroendocrine tumours.

OBJECTIVE: A comprehensive analysis of the immune landscape of pancreatic neuroendocrine tumours (PanNETs) was performed according to clinicopathological parameters and previously defined molecular subtypes to identify potential therapeutic vulnerabilities in this disease. DESIGN: Differential expression analysis of 600 immune-related genes was performed on 207 PanNET samples, comprising a training cohort (n=72) and two validation cohorts (n=135) from multiple transcriptome profiling platforms. Different immune-related and subtype-related phenotypes, cell types and pathways were investigated using different in silico methods and were further validated using spatial multiplex immunofluorescence. RESULTS: The study identified an immune signature of 132 genes segregating PanNETs (n=207) according to four previously defined molecular subtypes: metastasis-like primary (MLP)-1 and MLP-2, insulinoma-like and intermediate. The MLP-1 subtype (26%-31% samples across three cohorts) was strongly associated with elevated levels of immune-related genes, poor prognosis and a cascade of tumour evolutionary events: larger hypoxic and necroptotic tumours leading to increased damage-associated molecular patterns (viral mimicry), stimulator of interferon gene pathway, T cell-inflamed genes, immune checkpoint targets, and T cell-mediated and M1 macrophage-mediated immune escape mechanisms. Multiplex spatial profiling validated significantly increased macrophages in the MLP-1 subtype. CONCLUSION: This study provides novel data on the immune microenvironment of PanNETs and identifies MLP-1 subtype as an immune-high phenotype featuring a broad and robust activation of immune-related genes. This study, with further refinement, paves the way for future precision immunotherapy studies in PanNETs to potentially select a subset of MLP-1 patients who may be more likely to respond.

Reappraisal of a 2-Cm Cut-off Size for the Management of Cystic Pancreatic Neuroendocrine Neoplasms: A Multicenter International Study.

OBJECTIVE: The aim of this study was to characterize an international cohort of resected cystic pancreatic neuroendocrine neoplasms (cPanNENs) and identify preoperative predictors of aggressive behavior. BACKGROUND: The characteristics of cPanNENs are unknown and their clinical management remains unclear. An observational strategy for asymptomatic cPanNENs ≤2 cm has been proposed by recent guidelines, but evidence is scarce and limited to single-institutional series. METHODS: Resected cPanNENs (1995-2017) from 16 institutions worldwide were included. Solid lesions (>50% solid component), functional tumors, and MEN-1 patients were excluded. Aggressiveness was defined as lymph node (LN) involvement, G3 grading, distant metastases, and/or recurrence. RESULTS: Overall, 263 resected cPanNENs were included, among which 177 (63.5%) were >2 cm preoperatively. A preoperative diagnosis of cPanNEN was established in 162 cases (61.6%) and was more frequent when patients underwent endoscopic ultrasound [EUS, odds ratio (OR) 2.69, 95% confidence interval (CI) 1.52-4.77] and somatostatin-receptor imaging (OR 3.681, 95% CI 1.809-7.490), and for those managed in specialized institutions (OR 3.12, 95% CI 1.57-6.21). Forty-one cPanNENs (15.6%) were considered aggressive. In the whole cohort, LN involvement on imaging, age >65 years, preoperative size >2 cm, and pancreatic duct dilation were independently associated with aggressive behavior. In asymptomatic patients, older age and a preoperative size >2 cm remained independently associated with aggressiveness. Only 1 of 61 asymptomatic cPanNENs ≤2 cm displayed an aggressive behavior. CONCLUSIONS: The diagnostic accuracy of cPanNENs is increased by the use of EUS and somatostatin-receptor imaging and is higher in specialized institutions. Preoperative size >2 cm is independently associated with aggressive behavior. Consequently, a watch-and-wait policy for sporadic asymptomatic cPanNENs ≤2 cm seems justified and safe for most patients.