Faculty Bibliography

Importance/UNASSIGNED:While laparoscopic pancreaticoduodenectomy (LPD) is being adopted with increasing enthusiasm worldwide, it is still challenging for both technical and anatomical reasons. Currently, there is no consensus on the technical standards for LPD. Objective/UNASSIGNED:The aim of this consensus statement is to guide the continued safe progression and adoption of LPD. Evidence Review/UNASSIGNED:Summit on Minimally Invasive Pancreatico-Biliary Surgery in Wuhan, China. Findings/UNASSIGNED:Twenty-eight international experts from 8 countries constructed the expert panel. Sixteen statements were produced by the members of the expert panel. At least 80% of responders agreed with the majority (80%) of statements. Other than three randomized controlled trials published to date, most evidences were based on level 3 or 4 studies according to the AGREE II-GRS Instrument. Conclusions and Relevance/UNASSIGNED:The Wuhan international expert consensus meeting on LPD has produced a set of clinical practice statements for the safe development and progression of LPD. LPD is currently in its development and exploration stages, as defined by the international IDEAL framework for surgical innovation. More robust randomized controlled trial and registry study are essential to proceed with the assessment of LPD.

OBJECTIVE:PDAC patients who undergo surgical resection and receive effective chemotherapy have the best chance of long-term survival. Unfortunately, we lack predictive biomarkers to guide optimal systemic treatment. Ex-vivo generation of PDO for pharmacotyping may serve as predictive biomarkers in PDAC. The goal of the current study was to demonstrate the clinical feasibility of a PDO-guided precision medicine framework of care. METHODS:PDO cultures were established from surgical specimens and endoscopic biopsies, expanded in Matrigel, and used for high-throughput drug testing (pharmacotyping). Efficacy of standard-of-care chemotherapeutics was assessed by measuring cell viability after drug exposure. RESULTS:A framework for rapid pharmacotyping of PDOs was established across a multi-institutional consortium of academic medical centers. Specimens obtained remotely and shipped to a central biorepository maintain viability and allowed generation of PDOs with 77% success. Early cultures maintain the clonal heterogeneity seen in PDAC with similar phenotypes (cystic-solid). Late cultures exhibit a dominant clone with a pharmacotyping profile similar to early passages. The biomass required for accurate pharmacotyping can be minimized by leveraging a high-throughput technology. Twenty-nine cultures were pharmacotyped to derive a population distribution of chemotherapeutic sensitivity at our center. Pharmacotyping rapidly-expanded PDOs was completed in a median of 48 (range 18-102) days. CONCLUSIONS:Rapid development of PDOs from patients undergoing surgery for PDAC is eminently feasible within the perioperative recovery period, enabling the potential for pharmacotyping to guide postoperative adjuvant chemotherapeutic selection. Studies validating PDOs as a promising predictive biomarker are ongoing.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy characterized by extensive local invasion and systemic spread. In this study, we employed a three-dimensional organoid model of human pancreatic cancer to characterize the molecular alterations critical for invasion. Time-lapse microscopy was used to observe invasion in organoids from 25 surgically resected human PDAC samples in collagen I. Subsequent lentiviral modification and small-molecule inhibitors were used to investigate the molecular programs underlying invasion in PDAC organoids. When cultured in collagen I, PDAC organoids exhibited two distinct, morphologically defined invasive phenotypes, mesenchymal and collective. Each individual PDAC gave rise to organoids with a predominant phenotype, and PDAC that generated organoids with predominantly mesenchymal invasion showed a worse prognosis. Collective invasion predominated in organoids from cancers with somatic mutations in the driver gene SMAD4 (or its signaling partner TGFBR2). Reexpression of SMAD4 abrogated the collective invasion phenotype in SMAD4-mutant PDAC organoids, indicating that SMAD4 loss is required for collective invasion in PDAC organoids. Surprisingly, invasion in passaged SMAD4-mutant PDAC organoids required exogenous TGFβ, suggesting that invasion in SMAD4-mutant organoids is mediated through noncanonical TGFβ signaling. The Rho-like GTPases RAC1 and CDC42 acted as potential mediators of TGFβ-stimulated invasion in SMAD4-mutant PDAC organoids, as inhibition of these GTPases suppressed collective invasion in our model. These data suggest that PDAC utilizes different invasion programs depending on SMAD4 status, with collective invasion uniquely present in PDAC with SMAD4 loss. SIGNIFICANCE: Organoid models of PDAC highlight the importance of SMAD4 loss in invasion, demonstrating that invasion programs in SMAD4-mutant and SMAD4 wild-type tumors are different in both morphology and molecular mechanism.

BACKGROUND:Screening high-risk individuals (HRI) can detect potentially curable pancreatic ductal adenocarcinoma (PDAC) and its precursors. We describe the outcomes of high-risk individuals (HRI) after pancreatic resection of screen-detected neoplasms. METHODS:Asymptomatic HRI enrolled in the prospective Cancer of the Pancreas Screening (CAPS) studies from 1998 to 2014 based on family history or germline mutations undergoing surveillance for at least 6 months were included. Pathologic diagnoses, hospital length of stay, incidence of diabetes mellitus, operative morbidity, need for repeat operation, and disease-specific mortality were determined. RESULTS:Among 354 HRI, 48 (13.6%) had 57 operations (distal pancreatectomy (31), Whipple (20), and total pancreatectomy (6)) for suspected pancreatic neoplasms presenting as a solid mass (22), cystic lesion(s) (25), or duct stricture (1). The median length of stay was 7 days (IQR 5-11). Nine of the 42 HRI underwent completion pancreatectomy for a new lesion after a median of 3.8 years (IQR 2.5-7.6). Postoperative complications developed in 17 HRI (35%); there were no perioperative deaths. New-onset diabetes mellitus after partial resection developed in 20% of HRI. Fourteen PDACs were diagnosed, 11 were screen-detected, 10 were resectable, and 9 had an R0 resection. Metachronous PDAC developed in remnant pancreata of 2 HRI. PDAC-related mortality was 4/10 (40%), with 90% 1-year survival and 60% 5-year survival, respectively. CONCLUSIONS:Screening HRI can detect PDAC with a high resectability rate. Surgical treatment is associated with a relatively short length of stay and low readmission rate, acceptable morbidity, zero 90-day mortality, and significant long-term survival. CLINICAL TRIAL REGISTRATION NUMBER/BACKGROUND:NCT2000089.

OBJECTIVE:The aim of this study was to investigate the key molecular alterations in small primary pancreatic neuroendocrine tumors (PanNETs) associated with the development of liver metastases. BACKGROUND:Well-differentiated PanNETs with small size are typically indolent; however, a limited subset metastasize to the liver. METHODS:A total of 87 small primary PanNETs (<3 cm), including 32 metastatic cases and 55 nonmetastatic cases after a 5-year follow-up, were immunolabeled for DAXX/ATRX and analyzed for alternative lengthening of telomeres (ALT) by Fluorescence In Situ Hybridization. A subset of these cases, 24 that metastasized and 24 that did not metastasize, were assessed by targeted next-generation sequencing and whole-genome copy number variation. RESULTS:In the entire cohort, high Ki-67 (OR 1.369; 95% CI 1.121-1.673; P = 0.002), N-stage (OR 4.568; 95% CI 1.458-14.312; P = 0.009), and ALT-positivity (OR 3.486; 95% CI 1.093-11.115; P = 0.035) were independently associated with liver metastases. In the subset assessed by next-generation sequencing and copy number variation analysis, 3 molecular subtypes with differing risks of liver metastases were identified. Group 1 (n = 15; 73% metastasized) was characterized by recurrent chromosomal gains, CN-LOH, DAXX mutations, and ALT-positivity. Group 2 (n = 19; 42% metastasized, including 5 G1 tumors) was characterized by limited copy number alterations and mutations. Group 3 (n = 14; 35% metastasized) were defined by chromosome 11 loss. CONCLUSIONS:We identified genomic patterns of small PanNETs associated with a different risk for liver metastases. Molecular alterations, such as DAXX mutations, chromosomal gains, and ALT, are associated with an increased risk of metastasis in small PanNETs. Therefore, targeted sequencing and/or ALT analysis may help in the clinical decisions for these small PanNETs.

BACKGROUND:Solid pseudopapillary tumors (SPTs) are rare, benign tumors of the pancreas that present as heterogeneous masses. We sought to evaluate the short- and long-term outcomes of surgical resected SPTs. Patients managed via initial surveillance were compared to those who underwent upfront resection. METHODS:A prospectively maintained institutional database was used to identify patients who underwent surgical resection for a SPT between 1988 and 2018. Data on clinicopathological features and outcomes were collected and analyzed. RESULTS:Seventy-eight patients underwent surgical resection for SPT during the study period. The mean age was 34.0 ± 14.6 years and a majority were female (N = 67, 85.9%) and white (N = 46, 58.9%). Thirty patients (37.9%) were diagnosed incidentally. Imaging-based presumed diagnosis was SPT in 49 patients (62.8%). A majority were located in the body or tail of the pancreas (N = 47, 60.3%), and 48 patients (61.5%) underwent a distal pancreatectomy. The median tumor size was 4.0 cm (IQR, 3.0-6.0), nodal disease was present in three patients (3.9%), and R0 resection was performed in all patients. No difference was observed in clinicopathological features and outcomes between patients who were initially managed via surveillance and those who underwent upfront resection. None of the patients under surveillance had nodal disease or metastasis at the time of resection; however, one of them developed recurrence of disease 95.1 months after resection. At a median follow-up of 36.1 months (IQR, 8.1-62.1), 77 (%) patients were alive and one patient (1.3%) had a recurrence of disease at 95.1 months after resection and subsequently died due to disease. CONCLUSIONS:SPTs are rare pancreatic tumors that are diagnosed most frequently in young females. While a majority are benign and have an indolent course, malignant behavior has been observed. Surgical resection can result in exceptional outcomes.

OBJECTIVE:The purpose of this study is to determine preoperative factors that are predictive of malignancy in patients undergoing pancreatic resection for intraductal papillary mucinous neoplasms (IPMN). SUMMARY BACKGROUND DATA:IPMN of the pancreas may be precursor lesions to pancreatic cancer (PC) and represent a target for early diagnosis or prevention. While there has been much effort to define preoperative risk factors for malignant pathology, guidelines are ever-changing and controversy remains surrounding which patients would benefit most from resection. METHODS:We performed a retrospective analysis of 901 consecutive patients obtained from two tertiary referral centers who underwent pancreatic resection for histologically proven IPMN between 2004 and 2017. Collected data included patient demographic characteristics, preoperative symptoms, radiological findings, and laboratory data. RESULTS:Main pancreatic duct (MPD) dilatation was the only variable that was significantly associated with increased probability of malignancy (defined high-dysplasia or invasion) on both univariate and multivariate analysis. Even middle-range MPD dilatation from 5 mm to 9.9 mm (n = 286) was associated with increased odds of HG-IPMN (OR = 2.74; 95% CI = 1.80-4.16) and invasion (OR = 4.42; 95% CI = 2.55-7.66). MPD dilatation >10 mm (n = 150) had even greater odds of HG-IPMN (OR = 6.57; 95% CI = 3.94-10.98) and invasion (OR = 15.07; 95% CI = 8.21-27.65). A cutoff of 5 to 7 mm MPD diameter was determined to be the best predictor to discriminate between malignant and benign lesions. CONCLUSIONS:In agreement with current IPMN management guidelines, we found MPD dilatation, even low levels from 5 mm to 9.9 mm, to be the single best predictor of HG-IPMN or invasion, highlighting the critical role that MPD plays in the selection of surgical candidates.

OBJECTIVE:The aim of this study was to clarify the role of pancreatic surgery during the COVID-19 pandemic to optimize patients' and clinicians' safety and safeguard health care capacity. SUMMARY BACKGROUND DATA:The COVID-19 pandemic heavily impacts health care systems worldwide. Cancer patients appear to have an increased risk for adverse events when infected by COVID-19, but the inability to receive oncological care seems may be an even larger threat, particularly in case of pancreatic cancer. METHODS:An online survey was submitted to all members of seven international pancreatic associations and study groups, investigating the impact of the COVID-19 pandemic on pancreatic surgery using 21 statements (April, 2020). Consensus was defined as >80% agreement among respondents and moderate agreement as 60% to 80% agreement. RESULTS:A total of 337 respondents from 267 centers and 37 countries spanning 5 continents completed the survey. Most respondents were surgeons (n = 302, 89.6%) and working in an academic center (n = 286, 84.9%). The majority of centers (n = 166, 62.2%) performed less pancreatic surgery because of the COVID-19 pandemic, reducing the weekly pancreatic resection rate from 3 [interquartile range (IQR) 2-5] to 1 (IQR 0-2) (P < 0.001). Most centers screened for COVID-19 before pancreatic surgery (n = 233, 87.3%). Consensus was reached on 13 statements and 5 statements achieved moderate agreement. CONCLUSIONS:This global survey elucidates the role of pancreatic surgery during the COVID-19 pandemic, regarding patient selection for the surgical and oncological treatment of pancreatic diseases to support clinical decision-making and creating a starting point for further discussion.

INTRODUCTION:Improvement in imaging has resulted in frequent diagnosis of benign and premalignant pancreatic tumors. Pancreatic nerve sheath (PNS) tumors are one of the rarest pancreatic tumors. Literature on PNS is limited and their biology is poorly understood. Here, we report the largest series of PNS tumors to date and review the literature to evaluate the current data available on PNS tumors. METHODS:An institutional database was used to identify patients who underwent resection for PNS tumors. Clinicopathological characteristics and outcomes of these patients were reported. Furthermore, a review of literature was performed. RESULTS:From January 1994 through December 2016, seven patients underwent resection for PNS tumors. The median age was 57.7 years (IQR, 44.9-61.9) and the sex was approximately equally distributed (male = 4; 57.1%). Three (42.9%) patients were diagnosed incidentally and six (85.7%) were misdiagnosed as having other pancreatic tumors. The median tumor size was 2.1 (IQR 1.8-3.0) cm and six (85.7%) had no nodal disease. At a median follow-up of 15.5 (IQR 13.7-49.3) months, six patients were alive without evidence of disease and one patient was lost to follow-up. The literature review identified 49 studies reporting 54 patients with PNS tumors. Forty-six were misdiagnosed as having other pancreatic tumors. The median tumor size was 3.6 (range 1-20) cm, nodal disease was present in six patients (22.2%), and no patient had distant metastatic disease. At the time of last follow-up, all patients were free of disease. CONCLUSION:This is the largest single institution series on PNS tumors reported to date. These tumors are rare and are often misdiagnosed, given their radiological characteristics. PNS tumors have a benign course of disease and surgical resection results in favorable long-term outcomes.