Rare, Tightly-Bound, Multi-Cellular Clusters in the Pancreatic Ducts of Adult Mice Function Like Progenitor Cells and Survive and Proliferate After Acinar Cell Injury

Pancreatic ductal progenitor cells have been proposed to contribute to adult tissue maintenance and regeneration after injury, but the identity of such ductal cells remains elusive. Here, from adult mice, we identify a near homogenous population of ductal progenitor-like clusters, with an average of 8 cells per cluster. They are a rare subpopulation, about 0.1% of the total pancreatic cells, and can be sorted using a fluorescence-activated cell sorter with the CD133highCD71lowFSCmid-high phenotype. They exhibit properties in self-renewal and tri-lineage differentiation (including endocrine-like cells) in a unique 3-dimensional colony assay system. An in vitro lineage tracing experiment, using a novel HprtDsRed/+ mouse model, demonstrates that a single cell from a cluster clonally gives rise to a colony. Droplet RNAseq analysis demonstrates that these ductal clusters express embryonic multipotent progenitor cell markers Sox9, Pdx1, and Nkx6-1, and genes involved in actin cytoskeleton regulation, inflammation responses, organ development, and cancer. Surprisingly, these ductal clusters resist prolonged trypsin digestion in vitro, preferentially survive in vivo after a severe acinar cell injury and become proliferative within 14 days post-injury. Thus, the ductal clusters are the fundamental units of progenitor-like cells in the adult murine pancreas with implications in diabetes treatment and tumorigenicity.

Artificial intelligence in a prediction model for postendoscopic retrograde cholangiopancreatography pancreatitis

OBJECTIVES

In this study we aimed to develop an artificial intelligence-based model for predicting postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).

METHODS

We retrospectively reviewed ERCP patients at Nagoya University Hospital (NUH) and Toyota Memorial Hospital (TMH). We constructed two prediction models, a random forest (RF), one of the machine-learning algorithms, and a logistic regression (LR) model. First, we selected features of each model from 40 possible features. Then the models were trained and validated using three fold cross-validation in the NUH cohort and tested in the TMH cohort. The area under the receiver operating characteristic curve (AUROC) was used to assess model performance. Finally, using the output parameters of the RF model, we classified the patients into low-, medium-, and high-risk groups.

RESULTS

A total of 615 patients at NUH and 544 patients at TMH were enrolled. Ten features were selected for the RF model, including albumin, creatinine, biliary tract cancer, pancreatic cancer, bile duct stone, total procedure time, pancreatic duct injection, pancreatic guidewire-assisted technique without a pancreatic stent, intraductal ultrasonography, and bile duct biopsy. In the three fold cross-validation, the RF model showed better predictive ability than the LR model (AUROC 0.821 vs. 0.660). In the test, the RF model also showed better performance (AUROC 0.770 vs. 0.663, P = 0.002). Based on the RF model, we classified the patients according to the incidence of PEP (2.9%, 10.0%, and 23.9%).

CONCLUSION

We developed an RF model. Machine-learning algorithms could be powerful tools to develop accurate prediction models.

Endoscopic Nasopancreatic Drainage Contributes to Early Resolution of Postgastrectomy Gastropancreatic Fistula

A 76-year-old man experienced abdominal pain 43 days after gastric cancer resection. Computed tomography revealed a gastric wall defect extending to the pancreas, and endoscopic retrograde pancreatography revealed a gastropancreatic fistula. Afterward, a nasopancreatic duct drainage tube was inserted. Seven days later, no leakage of the contrast medium from the duct was observed, and the patient was discharged 22 days after endoscopic nasopancreatic duct drainage. Endoscopic nasopancreatic duct drainage prevents pancreatic juice leakage and promotes gastric ulcer healing.

Robotic versus open pancreatoduodenectomy in patients with pancreatic duct adenocarcinoma after the learning curve: a propensity score-matched analysis

BACKGROUND

Studies have demonstrated that the learning curve plays an important role in robotic pancreatoduodenectomy (RPD). Although improved short-term outcomes of RPD after the learning curve have been reported compared to open pancreatoduodenectomy (OPD), there is a lack of long-term survival analyses.

METHODS

Patients who underwent curative intended RPD and OPD for pancreatic duct adenocarcinoma (PDAC) between January 2017 and June 2020 were retrospectively reviewed. A 1:2 propensity score matching (PSM) analysis was performed to balance the baseline characteristics between the RPD and OPD groups.

RESULTS

Of the 548 patients (108 RPD and 440 OPD), 103 RPD patients were matched with 206 OPD patients after PSM. There were 194 (62.8%) men and 115 (37.2%) women, with a median age of 64 (58-69) years. The median overall survival (OS) in the RPD group was 33.2 months compared with 25.7 months in the OPD group (p = 0.058, log-rank). The median disease-free survival (DFS) following RPD was longer than the OPD (18.5 vs. 14.0 months, p = 0.011, log-rank). The RPD group has a lower incidence of local recurrence compared the OPD group (36.9% vs. 51.2%, p = 0.071). Multivariate Cox analysis demonstrated that RPD was independently associated with improved OS (HR 0.70, 95% CI 0.52-0.94, p = 0.019) and DFS (HR 0.66, 95% CI 0.50-0.88, p = 0.005).

CONCLUSION

After the learning curve, RPD had improved oncologic outcomes in PDAC patients compared to OPD. Future prospective randomized clinical trials will be required to validate these findings.

Does Congenital Biliary Dilatation Todani Type II (Diverticular Type) Really Exist?

AIM OF THE STUDY

The aim of the study is to clarify the clinicopathological and biliary morphological characteristics in reported cases of diverticular congenital biliary dilatation (CBD).

METHOD

Using PubMed and the Japan Medical Abstracts Society, articles on possible diverticular CBD were extracted and the clinical pictures examined. We also sought evidence for definitions of diverticular CBD and the associated condition of pancreaticobiliary maljunction (PBM) using the original articles by Alonso-Lej and Todani. The characteristic biliary morphologies of cases with images were also investigated.

RESULTS

Analyses of 211 possible cases superficially demonstrated multiple diverticula in 12 (12%) and single diverticulum in 89 (88%), with diverticula located in the upper (n = 38, 38%), middle (n = 32, 32%), or lower (n = 26, 26%) biliary tract in and presence of intra-diverticular stones, PBM, and biliary carcinoma in 23% (n = 18), 39% (n = 25), and 11% (n = 14), respectively. However, evidence defining diverticular CBD or justifying the lack of associated PBM was not demonstrated even in the original articles. Scrutiny of the biliary anatomy in 59 cases with images showed incorrect inclusions of types I or IV-A with an irregular biliary duct wall or dilated cystic duct, periampullary choledochal diverticula, or even solitary biliary cysts. Authentic diverticular CBD, representing the diverticulum connected to the middle of the common bile duct via a thin, patent stalk was seen in only 6 cases.

CONCLUSION

Real diverticular CBD appears extremely rare. The lack of an objective definition allows wide interpretations of clinical pictures, creating inconsistencies in the diagnosis and treatment of CBD and raising questions regarding the utility of conventional classifications.

LEVEL OF EVIDENCE

Level III.

Evaluation of a Novel Easy Loop-Forming Guidewire to Reduce Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis for Serial Pancreatic Juice Aspiration Cytologic Examination: A Propensity Score Matching Analysis

OBJECTIVE

This study aimed to investigate whether a novel, easy loop-forming guidewire could reduce post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) in patients undergoing endoscopic nasopancreatic drainage tube placement for serial pancreatic juice aspiration cytologic examination (SPACE).

METHODS

We evaluated patients with suspected pancreatic cancer who underwent SPACE at our institution between January 2015 and April 2023 retrospectively. The patients were divided into 2 groups based on the type of guidewire used, namely, easy loop-forming and control groups. Propensity score matching was used to compare the incidence of PEP between the groups.

RESULTS

We included 101 patients, with 51 and 50 in the easy loop-forming and control groups, respectively. After propensity score matching, 29 pairs of patients were selected from each group. Intraductal ultrasonography of the pancreas was performed more frequently in the easy loop-forming group than in the control group (27.6% vs 0%; P = 0.004); however, PEP incidence was significantly lower in the easy loop-forming group than in the control group (3.4% vs 27.6%; odds ratio, 0.097; 95% confidence interval, 0.002-0.82; P = 0.025).

CONCLUSIONS

The use of the novel easy loop-forming guidewire decreased PEP occurrence in patients who underwent endoscopic nasopancreatic drainage tube placement for SPACE.

Understanding bacterial infiltration of the pancreas through a deformable pancreatic duct

Tiny amount of bacteria are found in the pancreas in pancreatitis and cancer, which seemed involved in inflammation and carcinogenesis. However, bacterial infiltration from the duodenum is inhibited by the physical defense mechanisms such as bile flow and the sphincter of Oddi. To understand how the bacteria possibly infiltrate the pancreas through a deformable pancreatic duct, influenced by the periodic contractions of the sphincter of Oddi, a mathematical model of bacterial infiltration is developed that considered large deformation, fluid flow, and bacterial transport in a deformable pancreatic duct. In addition, the sphincter's contraction wave is modeled by including its propagation from the pancreas toward the duodenum. Simulated structure of the deformed duct with the relaxed sphincter and simulated bile distribution agreed reasonably well with the literature, validating the model. Bacterial infiltration from the duodenum in a deformable pancreatic duct, following the sphincter's contraction, is counteracted by a gradual peristalsis-like deformation of the pancreatic duct, due to an antegrade contraction wave propagation from the pancreas to the duodenum, Parametric sensitivity analysis demonstrated that bacterial infiltration is increased with lower bile and pancreatic juice flow rate, greater contraction amplitude and frequency, thinner wall thickness, and retrograde contraction wave propagation. Since contraction waves following retrograde propagation are increased in patients with common bile duct stones and pancreatitis, they may possibly be factors for continuum inflammation of pancreas. (224 words).

Generation and ex vivo culture of murine and human pancreatic ductal adenocarcinoma tissue slice explants

Traditional 2D/3D co-culture models typically do not reflect the cellular heterogeneity of pancreatic ductal adenocarcinoma (PDAC) tumors, while in vivo models can be slow and ill-suited to mechanistic investigations. Here, we present a protocol for culturing murine PDAC explants and a corresponding human PDAC model using tissue slice explants. We describe steps for sponge production, preparation of media and materials, tissue collection, and sectioning. We then detail procedures for explant plating, daily culture, and collection of samples.

Timing of ERCP after extracorporeal shock wave lithotripsy for large main pancreatic duct stones

BACKGROUND AND AIMS

Extracorporeal shock wave lithotripsy (ESWL) is performed to fragment large main pancreatic duct (MPD) stones in symptomatic patients. Subsequent endoscopic retrograde cholangiopancreatography (ERCP) is often performed to clear the stone fragments. Edema of surrounding tissue after ESWL theoretically affects the ability to perform ERCP. However, the optimal timing of ERCP after ESWL is not clearly defined. The aim of this study is to determine the efficacy and safety of same-day ERCP after ESWL and to determine if the timing of ERCP after ESWL affects outcomes.

METHODS

This is a retrospective study of consecutive patients from January, 2013 to September, 2019 who received ESWL for MPD stones at our center. Included patients received subsequent same-day ERCP under the same general anesthesia session or later session ERCP (1-30 days after ESWL). Demographics, anatomical findings, history, and outcomes were collected. Success was defined as complete or near complete (> 80%) stone fragmentation with clearance.

RESULTS

218 patients were treated with ESWL and subsequent ERCP. 133 (61.0%) received ERCP on the same day immediately after ESWL, while 85 (39.0%) returned for ERCP at a later day (median 3.0 days after ESWL). Baseline characteristics demonstrated patients who received same-day ERCP had a higher rate of pain at baseline (94.7% vs 87.1%, p = 0.045). Main outcomes demonstrated an overall successful MPD stone clearance rate of 90.4%, with similar rates between same-day ERCP and later session ERCP (91.7% vs 88.2%, p = 0.394). Additionally, successful cannulation at ERCP, adverse events, and post-procedure admission rates were similar.

CONCLUSIONS

Delaying ERCP to allow peripancreatic tissue recovery after ESWL does not affect outcomes. Same-day ERCP after ESWL is safe and effective.

Pancreatic duct pressure: A review of technical aspects and clinical significance

Pancreatic duct pressure (PDP) dynamics comprise an intricately modulated system that helps maintain homeostasis of pancreatic function. It is affected by various factors, including the rate of pancreatic fluid secretion, patency of the ductal system, sphincter of Oddi function, and pancreatic fluid characteristics. Disease states such as acute and chronic pancreatitis can alter the normal PDP dynamics. Ductal hypertension or increased PDP is suspected to be involved in the pathogenesis of pancreatic pain, endocrine and exocrine pancreatic insufficiency, and recurrent pancreatitis. This review provides a comprehensive appraisal of the available literature on PDP, including the methods used in the measurement and clinical implications of elevated PDP.

Current status of and future issues related to endoscopic papillectomy

Endoscopic papillectomy is widely performed to treat duodenal papillary tumors, particularly at high-volume centers. It is indicated for adenomas without intraductal extension of the bile or pancreatic ducts. However, despite numerous reports of carcinomas that expand the indications to include well-differentiated adenocarcinomas that do not invade the sphincter of Oddi, the low agreement between biopsy and final pathological diagnosis, as well as the current inability of imaging modalities to diagnose sphincter of Oddi invasion, makes it difficult to consider expanding indications. Although complications can be prevented by certain methods, such as pancreatic duct stenting, and the frequency of severe complications has decreased, the safety of the procedure remains unconfirmed. In the future, this technology is expected to progress and enable wider applications, including those in tumors with extensive horizontal spread and those with intraductal extension of the bile and pancreatic ducts. Such technology may also improve the safety and accuracy of diagnosis.

Adverse events of pancreatic extracorporeal shock wave lithotripsy: a literature review

Pancreatic stones are the result of pathophysiologic changes in chronic pancreatitis with an incidence of more than 90%. At present, pancreatic extracorporeal shock wave lithotripsy (P-ESWL) can be used as the first-line treatment for large or complex stones. Although a large number of studies have proven the safety and effectiveness of P-ESWL, we should also pay attention to postoperative adverse events, mainly due to the scattering of shock waves in the conduction pathway. Adverse events can be classified as either complications or transient adverse events according to the severity. Because the anatomic location of organs along the shock wave conducting pathway differs greatly, adverse events after P-ESWL are varied and difficult to predict. This paper outlines the mechanism, definition, classification, management and risk factors for adverse events related to P-ESWL. It also discusses the technique of P-ESWL, indications and contraindications of P-ESWL, and adverse events in special populations.

Clinical trajectory of intraductal papillary mucinous neoplasms progressing to pancreatic carcinomas during long-term surveillance: a prospective series of 100 carcinoma cases

BACKGROUND

Trajectories of serological and morphological signatures have not been documented in pancreatic carcinogenesis related to intraductal papillary mucinous neoplasms (IPMNs).

METHODS

Using a prospective cohort of 3437 IPMN patients, we identified 100 IPMN patients who developed pancreatic carcinomas during long-term surveillance. We examined serial changes of blood markers (carbohydrate antigen 19-9 [CA19-9], hemoglobin A1c [HbA1c], and pancreatic enzymes) and morphological features (worrisome features and high-risk stigmata) during the prediagnostic period of pancreatic carcinomas, overall and by carcinoma types (IPMN-derived vs. concomitant pancreatic carcinomas).

RESULTS

CA19-9 elevation was observed in 39 patients and was associated with a metastatic stage. Compared to IPMN-derived carcinomas, concomitant carcinomas were more likely to represent CA19-9 elevation (60% vs. 30%, respectively; P = 0.005). HbA1c levels elevated only in 3 patients. Pancreatic enzyme elevation was observed in 18 patients with no differences in frequencies between the carcinoma types. All patients with elevated levels of blood markers had positive findings on cross-sectional imaging. High-risk stigmata or worrisome features were observed in all patients but one with concomitant carcinoma. The most common types of worrisome features were the main pancreatic duct dilatation and CA19-9 elevation in IPMN-derived and concomitant carcinomas, respectively. Compared to IPMN-derived carcinomas, concomitant carcinomas were less likely to harbor high-risk stigmata (16% vs. 86%, respectively; P < 0.001).

CONCLUSIONS

The usefulness of currently available blood biomarkers was limited in early detection of pancreatic carcinomas related to IPMNs. Morphological alterations were well correlated with long-term risk of IPMN-derived carcinomas, but not with that of concomitant carcinomas.

Anemia, Iron Deficiency, and Iron Regulators in Pancreatic Ductal Adenocarcinoma Patients: A Comprehensive Analysis

Anemia and iron deficiency (ID) are common complications in patients with pancreatic ductal adenocarcinoma (PDAC), but their underlying causes remain unclear. This study investigated the incidence and characteristics of anemia and micronutrient deficiencies in PDAC patients before initiating chemotherapy. A total of 103 PDAC patients were included, comprising 67 in the palliative and 36 in the adjuvant groups. The overall incidence of anemia was 42.7% (n = 44), with comparable rates in both groups. Normocytic and normochromic anemia were predominant, with mild and moderate cases observed in 32% and 10.7% of the cohort, respectively. ID was evident in 51.4% of patients, with absolute ID more frequent in the adjuvant than in the palliative group (19.4% vs. 13.4%). Functional ID occurred more often in the palliative than in the adjuvant group (41.8% vs. 25%). Vitamin B12 and folate deficiency occurred in <5% (n = 5) of patients. Furthermore, 8.7% (n = 9) of patients had chronic kidney disease and anemia. To elucidate mechanisms of iron deficiency, the study explored the expression of iron regulators (hepcidin (HEP), ferroportin (FPN), and ZIP14 protein) and mitochondrial mass in PDAC tissue with immunohistochemical (IHC) staining and Perl's Prussian blue to detect iron deposits on available tumor samples (n = 56). ZIP14 expression was significantly higher in less advanced tumors (p = 0.01) and correlated with mitochondrial mass (p < 0.001), potentially indicating its role in local iron homeostasis. However, no significant impact of tissue iron regulators on patient survival was observed. Perl's Prussian blue staining revealed iron deposits within macrophages, but not in pancreatic duct cells. Furthermore, the GEPIA database was used to compare mRNA expression of iron regulators (HEP, FPN, and ZIP14) and other genes encoding iron transport and storage, including Transferrin Receptor Protein 1 (TfR1) and both ferritin chain subunits (FTH and FTL), in PDAC and normal pancreatic samples. FPN, TfR1, FTH, and FTL showed higher expression in tumor tissues, indicating increased iron usage by cancer. ZIP14 expression was higher in the pancreas than in PDAC and was correlated with FPN expression. The study highlights the importance of baseline iron status assessment in managing PDAC patients due to the high incidence of anemia and iron deficiency. Furthermore, ZIP14, in addition to HEP and FPN, may play a crucial role in local iron homeostasis in PDAC patients, providing valuable insights into the underlying mechanisms of iron dysregulation.

Bounding box-based 3D AI model for user-guided volumetric segmentation of pancreatic ductal adenocarcinoma on standard-of-care CTs

OBJECTIVES

To develop a bounding-box-based 3D convolutional neural network (CNN) for user-guided volumetric pancreas ductal adenocarcinoma (PDA) segmentation.

METHODS

Reference segmentations were obtained on CTs (2006-2020) of treatment-naïve PDA. Images were algorithmically cropped using a tumor-centered bounding box for training a 3D nnUNet-based-CNN. Three radiologists independently segmented tumors on test subset, which were combined with reference segmentations using STAPLE to derive composite segmentations. Generalizability was evaluated on Cancer Imaging Archive (TCIA) (n = 41) and Medical Segmentation Decathlon (MSD) (n = 152) datasets.

RESULTS

Total 1151 patients [667 males; age:65.3 ± 10.2 years; T1:34, T2:477, T3:237, T4:403; mean (range) tumor diameter:4.34 (1.1-12.6)-cm] were randomly divided between training/validation (n = 921) and test subsets (n = 230; 75% from other institutions). Model had a high DSC (mean ± SD) against reference segmentations (0.84 ± 0.06), which was comparable to its DSC against composite segmentations (0.84 ± 0.11, p = 0.52). Model-predicted versus reference tumor volumes were comparable (mean ± SD) (29.1 ± 42.2-cc versus 27.1 ± 32.9-cc, p = 0.69, CCC = 0.93). Inter-reader variability was high (mean DSC 0.69 ± 0.16), especially for smaller and isodense tumors. Conversely, model's high performance was comparable between tumor stages, volumes and densities (p > 0.05). Model was resilient to different tumor locations, status of pancreatic/biliary ducts, pancreatic atrophy, CT vendors and slice thicknesses, as well as to the epicenter and dimensions of the bounding-box (p > 0.05). Performance was generalizable on MSD (DSC:0.82 ± 0.06) and TCIA datasets (DSC:0.84 ± 0.08).

CONCLUSION

A computationally efficient bounding box-based AI model developed on a large and diverse dataset shows high accuracy, generalizability, and robustness to clinically encountered variations for user-guided volumetric PDA segmentation including for small and isodense tumors.

CLINICAL RELEVANCE

AI-driven bounding box-based user-guided PDA segmentation offers a discovery tool for image-based multi-omics models for applications such as risk-stratification, treatment response assessment, and prognostication, which are urgently needed to customize treatment strategies to the unique biological profile of each patient's tumor.

Frequent guidewire passage into the pancreatic duct is an independent risk factor for postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) among high-risk individuals: A post-hoc analysis of a randomized controlled trial data

OBJECTIVES

To systematically evaluate the patient and procedural risk factors for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) among patients receiving rectal indomethacin.

METHODS

Data from a randomized controlled trial (RCT) of high-risk patients undergoing ERCP who received rectal indomethacin with or without topical epinephrine was evaluated. PEP was defined based on the consensus criteria. Pancreatic stenting was excluded to avoid confounding results with the role of epinephrine spray. Multivariable logistic regression analysis was used to identify patient and procedural risk factors for PEP.

RESULTS

Among 960 patients enrolled in the RCT, the PEP incidence was 6.4%. An increased risk of PEP was seen with age <50 years and female gender (odds ratio [OR] 2.40, 95% confidence interval [CI] 1.35-4.26), malignant biliary stricture(s) (OR 3.51, 95% CI 1.52-8.10), >2 guidewire passes into the pancreatic duct (PD) (OR 2.84, 95% CI 1.43-5.64), and pancreatic brush cytology (OR 6.37, 95% CI 1.10-36.90), whereas a decreased risk of PEP was seen with contrast- over guidewire-assisted cannulation (OR 0.14, 95% CI 0.02-0.99) and the use of lactated Ringer's (LR) over other fluid types (OR 0.52, 95% CI 0.27-0.98). There was a significant trend between the number of guidewire passes into the PD and PEP risk (P = 0.002).

CONCLUSIONS

More than two guidewire passes into the PD and pancreatic brush cytology increased while the use of LR decreased the risk of PEP among high-risk patients receiving rectal indomethacin. Pancreatic stent placement and/or LR should be considered in patients with >2 guidewire passes into the PD.

Utilization pattern of prophylactic measures for prevention of post-ERCP pancreatitis: a National Survey Study

BACKGROUND AND AIMS

Post-ERCP pancreatitis (PEP) is the most frequent adverse event of ERCP. Various prophylactic measures are endorsed by the American Society for Gastrointestinal Endoscopy and the European Society of Gastrointestinal Endoscopy to both lower the incidence of PEP and to decrease its severity. The extent to which these interventions are practiced throughout the United States is unclear. The aim of this study was to describe the utilization pattern of various PEP measures and determine factors that affect utilization of these measures.

METHODS

A 27-question electronic survey was distributed using a cloud-based program (Qualtrics). The questions assessed ERCP training, practice setting, experience, practice patterns, and perceptions for PEP prophylaxis interventions. Endoscopists with practices based in the United States listed in the American Society for Gastrointestinal Endoscopy member directory received a survey invitation via e-mail. The invitation outlined the study and contained a link with instructions to complete the voluntary survey if they had an active ERCP practice. Data were de-identified for the purposes of analysis.

RESULTS

Of survey respondents (N = 319), 46% reported therapeutic endoscopy fellowship training and 37% practiced in teaching programs. Annualized ERCP volume of >100 cases per year were reported by 47%, with pancreatic ERCP comprising ≤5% of procedure volume reported by the majority of respondents (61%). The majority of respondents used prophylactic pancreatic stent (PPS), and 54% reported frequent use during high-risk ERCP. The most common indications for PPS were difficult cannulation, to assist biliary access, and multiple pancreatic duct injections. Most respondents reported frequent use of indomethacin (89%). Of physicians who did not use PPS, use of indomethacin was the most common reason (80%). Variables associated with frequent use of PPS were ERCP fellowship training (P ≤ .001), practice at a teaching program (P ≤ .001), <10 years in practice (P = .005), higher procedure volume (P ≤ .001), and higher proportion of pancreatic cases (P ≤ .001).

CONCLUSIONS

Physicians with higher annual ERCP volume, who teach at hospital-based ERCP practices, and who regularly perform pancreatic ERCP are more likely to use PPS. Therapeutic ERCP fellowship training and recent entry into practice were also associated with PPS utilization. Indomethacin use seems to be more frequent than PPS. Our findings suggest that indomethacin is supplanting PPS as the preferred method of PEP prophylaxis.

Universal prophylactic rectal nonsteroidal anti-inflammatory drugs with a policy of selective pancreatic duct stenting significantly reduce post-endoscopic retrograde cholangiopancreatography pancreatitis

BACKGROUND

Although rectal nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to be effective for the prevention of post-ERCP (endoscopic retrograde cholangiopancreatography) pancreatitis (PEP) in high-risk patients, the benefit in average-risk patients is unclear. We aimed at assessing the benefit of prophylactic rectal NSAIDs in unselected consecutive patients to prevent PEP.

METHODS

All patients undergoing index ERCP procedures from January 2018 until March 2020 were included. All patients received prophylactic rectal diclofenac. A prophylactic pancreatic duct (PD) stent was placed if there was repeated PD cannulation, at the discretion of the endoscopist. The frequency of PEP was compared with historical controls.

RESULTS

Of 769 patients who underwent ERCP, 34 (4.4%) developed PEP (mild in 29 [85.3%], moderate in four [11.8%] and severe in one [2.9%]). Female gender, precut sphincterotomy, inadvertent PD cannulation and procedural time of > 30 minutes predicted PEP in univariate analysis. Inadvertent PD cannulation (OR 4.6, 95% CI: 1.8-11.7; p < 0.001) and procedural time of > 30 minutes (OR 8.5, 95% CI: 3.7-10.1; p < 0.001) were independent risk factors on multivariate analysis. When compared with historical controls, the odds of PEP with prophylactic use of rectal NSAIDs and selective PD stenting was 0.54 (CI: 0.31-0.93, p = 0.027). The number needed to treat (NNT) was 22 to prevent one PEP with prophylactic rectal NSAIDs.

CONCLUSION

Routine use of prophylactic rectal NSAIDs effectively prevents the occurrence of PEP in unselected consecutive patients in a real-world scenario.

Cost-effectiveness of Early Surgery Versus Endoscopy-first Approach for Painful Chronic Pancreatitis in the ESCAPE Trial

OBJECTIVE

Economic evaluation of early surgery compared to the endoscopy-first approach in CP.

BACKGROUND

In patients with painful CP and a dilated main pancreatic duct, early surgery, as compared with an endoscopy-first approach, leads to more pain reduction with fewer interventions. However, it is unknown if early surgery is more cost-effective than the endoscopy-first approach.

METHODS

The multicenter Dutch ESCAPE trial randomized patients with CP and a dilated main pancreatic duct between early surgery (surgery within 6 weeks) or the endoscopy-first approach in 30 centers (April 2011-September 2016). Healthcare utilization was prospectively recorded up to 18 months after randomization. Unit costs of resources were determined, and cost-effectiveness and cost-utility analyses were performed from societal and healthcare perspectives. Primary outcomes were the costs per unit decrease on the Izbicki pain score and per gained quality-adjusted life-year.

RESULTS

In total, 88 patients were included in the analysis, with 44 patients randomized to each group. Total costs were lower in the early surgery group but did not reach statistical significance (mean difference €-4,815 (95% bias-corrected and accelerated confidence interval €-13,113 to €3411; P = 0.25). Early surgery had a probability percentage of 88.4% of being more cost-effective than the endoscopy-first approach at a willingness-to-pay threshold of €0 per day per unit decrease on the Izbicki pain score. The probability percentage per additional gained quality-adjusted life-year was 75.7% at a willingness-to-pay threshold of €50,000.

CONCLUSION

In patients with painful CP and a dilated main pancreatic duct, early surgery was more cost-effective than the endoscopy-first approach.

Protocol to culture and image pancreatic ductal adenocarcinoma tumor slices to study T cell migration

Here, we describe a protocol for culture and live cell imaging of tumor slices. This approach studies carcinoma and immune cell dynamics in complex tumor microenvironments (TME) with nonlinear optical imaging platforms. Using a tumor-bearing mouse model of pancreatic ductal adenocarcinoma (PDA), we detail steps to isolate, activate, and label CD8+ T lymphocytes and later introduce them to live murine PDA tumor slice explants. The techniques described in this protocol can improve our understanding of cell migration in complex microenvironments ex vivo. For complete details on the use and execution of this protocol, please refer to Tabdanov et al. (2021).1.

Methylcellulose colony assay and single-cell micro-manipulation reveal progenitor-like cells in adult human pancreatic ducts

Progenitor cells capable of self-renewal and differentiation in the adult human pancreas are an under-explored resource for regenerative medicine. Using micro-manipulation and three-dimensional colony assays we identify cells within the adult human exocrine pancreas that resemble progenitor cells. Exocrine tissues were dissociated into single cells and plated into a colony assay containing methylcellulose and 5% Matrigel. A subpopulation of ductal cells formed colonies containing differentiated ductal, acinar, and endocrine lineage cells, and expanded up to 300-fold with a ROCK inhibitor. When transplanted into diabetic mice, colonies pre-treated with a NOTCH inhibitor gave rise to insulin-expressing cells. Both colonies and primary human ducts contained cells that simultaneously express progenitor transcription factors SOX9, NKX6.1, and PDX1. In addition, in silico analysis identified progenitor-like cells within ductal clusters in a single-cell RNA sequencing dataset. Therefore, progenitor-like cells capable of self-renewal and tri-lineage differentiation either pre-exist in the adult human exocrine pancreas, or readily adapt in culture.

Extracorporeal shockwave lithotripsy in combination with endoscopy as a treatment modality for painful chronic obstructive pancreatitis – a case report

Chronic pancreatitis (CP) is a serious condition with a great impact on the quality of life, and it can lead to some serious long-term consequences such as pancreatic cancer or secondary diabetes mellitus. Associated pancreatic exocrine insufficiency leads to malnutrition with weight loss; however, the main symptom of the disease is abdominal pain, often very severe. The primary treatment option for painful CP is pharmacotherapy (pancreatic enzyme replacement therapy, analgesics). If this is not effective, CP can be treated via endoscopy, extracorporeal shockwave lithotripsy (ESWL), their combination, or surgery. We present a case of painful chronic obstructive pancreatitis in a patient successfully treated with ESWL in combination with endoscopy.

[Acute pancreatitis triggered by an impacted minor papillary stone in a patient with pancreas divisum improved after spontaneous evacuation of the pancreatic stone:a case report]

A 56-year-old woman with epigastric pain was admitted to our hospital. Blood tests and abdominal computed tomography (CT) suggested acute pancreatitis. Abdominal CT revealed a pancreas divisum and stone in the minor papilla. Stone impaction was the most likely cause of the acute pancreatitis. The patient's abdominal pain promptly improved after admission. The patient was treated conservatively, and the pancreatitis resolved. Abdominal CT on the 10th day confirmed spontaneous evacuation of the pancreatic stone. This is a rare case of acute pancreatitis in a patient with pancreas divisum triggered by an impacted stone in the minor papilla, which improved after spontaneous evacuation of the pancreatic stone.

The effect of CT texture-based analysis using machine learning approaches on radiologists' performance in differentiating focal-type autoimmune pancreatitis and pancreatic duct carcinoma

PURPOSE

To develop a support vector machine (SVM) classifier using CT texture-based analysis in differentiating focal-type autoimmune pancreatitis (AIP) and pancreatic duct carcinoma (PD), and to assess the radiologists' diagnostic performance with or without SVM.

MATERIALS AND METHODS

This retrospective study included 50 patients (20 patients with focal-type AIP and 30 patients with PD) who underwent dynamic contrast-enhanced CT. Sixty-two CT texture-based features were extracted from 2D images of the arterial and portal phase CTs. We conducted data compression and feature selections using principal component analysis (PCA) and produced the SVM classifier. Four readers participated in this observer performance study and the statistical significance of differences with and without the SVM was assessed by receiver operating characteristic (ROC) analysis.

RESULTS

The SVM performance indicated a high performance in differentiating focal-type AIP and PD (AUC = 0.920). The AUC for all 4 readers increased significantly from 0.827 to 0.911 when using the SVM outputs (p = 0.010). The AUC for inexperienced readers increased significantly from 0.781 to 0.905 when using the SVM outputs (p = 0.310). The AUC for experienced readers increased from 0.875 to 0.912 when using the SVM outputs, however, there was no significant difference (p = 0.018).

CONCLUSION

The use of SVM classifier using CT texture-based features improved the diagnostic performance for differentiating focal-type AIP and PD on CT.

Risk of pancreatic ductal adenocarcinoma associated with carriage of BRCA1 and/or BRCA2 mutation: A systematic review and meta-analysis

Germline BRCA1/2 mutations lead to malfunction of DNA damage repair pathways and predispose to pancreatic ductal adenocarcinoma (PDAC). The aim of this study is to synthesise the available research on this topic. Four studies reporting risk ratio (RR) were included in the final meta-analysis to minimise misrepresenting our results by combining separate risk estimates. Our meta-analysis revealed a statistically significant increased risk of PDAC in BRCA carriers overall (RR: 2.65, 95% confidence interval: 1.43-4.91, p = 0.002).

Nonsurgical treatment for asymptomatic pancreatolithiasis is meaning: A case report

BACKGROUND

Many guidelines for nonsurgical treatment of pancreatolithiasis suggest little guidance for patients with pancreatolithiasis who do not have abdominal pain. Some patients with pancreatolithiasis whom we have treated nonsurgically with extracorporeal shock-wave lithotripsy did not have abdominal pain, and we describe one of them here.

METHODS AND RESULTS

A 42-year-old man complaining of an 8-kg weight loss over 6 months was admitted to a nearby hospital, where fasting blood sugar and hemoglobin A1c values were 500 mg/dL and 11.8%. Computed tomography showed stones in the head of the pancreas and dilation of the main pancreatic duct. He was referred to our hospital to be considered for nonsurgical treatment of pancreatolithiasis. His height and weight were 160 cm and 52 kg (body mass index, 20.31). No tenderness or other abdominal findings were evident. After obtaining informed consent for nonsurgical treatment despite absence of abdominal pain, we performed extracorporeal shock wave lithotripsy. Computed tomography showed disappearance of stones from the pancreatic head. At discharge, his weight had increased to 62 kg and hemoglobin A1c was 6.8%, though antidiabetic medication has since become necessary.

CONCLUSION

We believe that nonsurgical treatment of pancreatolithiasis was helpful for this patient, and could improve exocrine and endocrine function in other patients without abdominal pain.

Systematic Comparison of Pancreatic Ductal Adenocarcinoma Models Identifies a Conserved Highly Plastic Basal Cell State

Intratumoral heterogeneity and cellular plasticity have emerged as hallmarks of cancer, including pancreatic ductal adenocarcinoma (PDAC). As PDAC portends a dire prognosis, a better understanding of the mechanisms underpinning cellular diversity in PDAC is crucial. Here, we investigated the cellular heterogeneity of PDAC cancer cells across a range of in vitro and in vivo growth conditions using single-cell genomics. Heterogeneity contracted significantly in two-dimensional and three-dimensional cell culture models but was restored upon orthotopic transplantation. Orthotopic transplants reproducibly acquired cell states identified in autochthonous PDAC tumors, including a basal state exhibiting coexpression and coaccessibility of epithelial and mesenchymal genes. Lineage tracing combined with single-cell transcriptomics revealed that basal cells display high plasticity in situ. This work defines the impact of cellular growth conditions on phenotypic diversity and uncovers a highly plastic cell state with the capacity to facilitate state transitions and promote intratumoral heterogeneity in PDAC.

SIGNIFICANCE

This work provides important insights into how different model systems of pancreatic ductal adenocarcinoma mold the phenotypic space of cancer cells, highlighting the power of in vivo models.

Black pleural effusion caused by a pancreaticopleural fistula associated with autoimmune pancreatitis: A case report

RATIONALE

Black pleural effusion is a rare medical condition and a diagnostic marker. Pancreaticopleural fistula is one of the causes of black pleural effusion. Thus far, black pleural effusions caused by pancreaticopleural fistulae have mostly been reported in patients with alcohol-induced chronic pancreatitis. In this report, we present a case of black pleural effusion caused by a pancreaticopleural fistula associated with autoimmune pancreatitis.

PATIENT CONCERNS AND DIAGNOSIS

A 59-year-old female without a history of alcohol drinking presented to our hospital with a chief complaint of dyspnea, as well as chest and back discomfort. She had left pleural effusion, and thoracentesis showed black pleural effusion. Computed tomography revealed the presence of encapsulated fluid from the pancreatic tail to the left pleural cavity, which was diagnosed as a pancreaticopleural fistula. It also showed diffuse pancreatic swelling. Serum testing showed a high IgG4 level (363 mg/dL). These findings led to the diagnosis of autoimmune pancreatitis.

INTERVENTIONS AND OUTCOME

The patient underwent endoscopic pancreatic sphincterotomy and pancreatic duct stent placement and received treatment with steroids. After treatment, there was no further accumulation of pleural effusion observed.

CONCLUSION

This is the first report of black pleural effusion due to a pancreaticopleural fistula associated with autoimmune pancreatitis. The characteristic appearance of black pleural effusion may assist diagnosis. We report this case to emphasize that autoimmune pancreatitis can be a cause of black pleural effusion.

Lung contusion after extracorporeal shock wave lithotripsy for pancreatic stones: A case report

BACKGROUND

Pancreatic extracorporeal shock wave lithotripsy (P-ESWL) is recommended as the first-line treatment for large pancreatic stones. While complications such as post-P-ESWL pancreatitis, bleeding, infection, steinstrasse, and perforation have been reported in the past 30 years, lung contusion has never been reported. The present case demonstrates lung contusion as a complication after P-ESWL.

METHODS

A 48-year-old man was admitted to our department due to painful chronic pancreatitis with pancreatic duct stones. Computed tomography revealed normal lungs. P-ESWL was performed. The shock wave head contacted with right upper quadrant and the path of shock wave was at a 45° angle to the ventral midline. After P-ESWL, multiple patchy high-density shadows in the lower lobe of right lung were found, which was normal before P-ESWL. The patient had no symptoms of lung injury.

RESULTS AND CONCLUSION

Laboratory studies revealed elevated D-dimer from 0.33 to 0.74 ug/mL, which was consistent with abnormal clotting of lung contusion. Chest computed tomography showed slight pleural effusion. Considering the interval between 2 X-rays was only 3 hours, we inferred that lung contusion was related to P-ESWL. The patient displayed stable vital signs, therefore, no specific interventions were conducted. Three days after P-ESWL, endoscopic retrograde cholangiopancreatography was performed and the lung shadows were partially absorbed. Considering the location of shock wave head, it was possible to cause lung contusion in lower lobe of right lung. More than 10,000 P-ESWL therapeutic sessions had been performed in our center since 2010, and it is the first case about lung contusion as a complication. It is also the first report to describe lung contusion after P-ESWL. Although the patient was asymptomatic, it should raise awareness of clinicians.

Hemosuccus Pancreaticus: A Rare Cause of Gastrointestinal Bleeding

Hemosuccus pancreaticus or bleeding from the pancreatic duct into the gastrointestinal tract via the ampulla of Vater is caused by rupture of the pseudoaneurysm of a peripancreatic vessel into pancreatic duct or pancreatic pseudocyst in the context of pancreatitis or pancreatic tumour or trauma. It produces diagnostic and therapeutic dilemma due to its anatomical location and that bleeding into the duodenum is intermittent and cannot be easily diagnosed by endoscopy, often needs CE-CT and angiography. In August 2019, a 60-year-old male presented with intermittent abdominal pain, gastrointestinal bleeding and high serum lipase. Upper GIT endoscopy showed blood mixed bile coming out through ampulla, suspecting Hemosuccus pancreaticus. Contrast-enhanced computed tomography (CT) scan demonstrated pancreatic pseudo cyst with partially thrombosed splenic artery pseudoaneurysm. At laparotomy, splenic artery pseudoaneurysm was ligated along with splenectomy. Later on, the patient had no further occurrence of gastrointestinal bleeding.

Spatial and transcriptional heterogeneity of pancreatic beta cell neogenesis revealed by a time-resolved reporter system

AIMS/HYPOTHESIS

While pancreatic beta cells have been shown to originate from endocrine progenitors in ductal regions, it remains unclear precisely where beta cells emerge from and which transcripts define newborn beta cells. We therefore investigated characteristics of newborn beta cells extracted by a time-resolved reporter system.

METHODS

We established a mouse model, 'Ins1-GFP; Timer', which provides spatial information during beta cell neogenesis with high temporal resolution. Single-cell RNA-sequencing (scRNA-seq) was performed on mouse beta cells sorted by fluorescent reporter to uncover transcriptomic profiles of newborn beta cells. scRNA-seq of human embryonic stem cell (hESC)-derived beta-like cells was also performed to compare newborn beta cell features between mouse and human.

RESULTS

Fluorescence imaging of Ins1-GFP; Timer mouse pancreas successfully dissected newly generated beta cells as green fluorescence-dominant cells. This reporter system revealed that, as expected, some newborn beta cells arise close to the ducts (β^duct); unexpectedly, the others arise away from the ducts and adjacent to blood vessels (β^vessel). Single-cell transcriptomic analyses demonstrated five distinct populations among newborn beta cells, confirming spatial heterogeneity of beta cell neogenesis such as high probability of glucagon-positive β^duct, musculoaponeurotic fibrosarcoma oncogene family B (MafB)-positive β^duct and musculoaponeurotic fibrosarcoma oncogene family A (MafA)-positive β^vessel cells. Comparative analysis with scRNA-seq data of mouse newborn beta cells and hESC-derived beta-like cells uncovered transcriptional similarity between mouse and human beta cell neogenesis including microsomal glutathione S-transferase 1 (MGST1)- and synaptotagmin 13 (SYT13)-highly-expressing state.

CONCLUSIONS/INTERPRETATION

The combination of time-resolved histological imaging with single-cell transcriptional mapping demonstrated novel features of spatial and transcriptional heterogeneity in beta cell neogenesis, which will lead to a better understanding of beta cell differentiation for future cell therapy.

DATA AVAILABILITY

Raw and processed single-cell RNA-sequencing data for this study has been deposited in the Gene Expression Omnibus under accession number GSE155742.

Pancreatic Stones: Clinical Outcomes With Nonsurgical Treatment in a Japanese Single-Center Study

OBJECTIVES

While chronic pancreatitis associated with pancreatolithiasis presents with pain, exocrine and endocrine pancreatic functions worsen with time. We examined outcomes of nonsurgical treatment.

METHODS

Between 1992 and 2020, we treated pancreatolithiasis nonsurgically in 165 patients with chronic pancreatitis using extracorporeal shock wave lithotripsy alone or followed by endoscopic procedures. The mean follow-up duration was 49 months (standard deviation, 56 months) and the age was 56 years (standard deviation, 13 years). The male:female ratio was 5.1:1 (138 men, 27 women). We followed treatment results including relief of abdominal pain, stone clearance and recurrence, and pancreatic exocrine function (bentiromide-p-aminobenzoic acid testing).

RESULTS

Treatment relieved pain in 117 of 124 patients (94%). The overall stone clearance was achieved in 130 of 165 patients (79%). Stones recurred during follow-up in 50 of 130 patients (38%). One fifth of recurrences were early, often involving stricture of the main pancreatic duct. After 1 year, 65% of the patients had improved or stable exocrine function.

CONCLUSIONS

Nonsurgical stone removal usually improved symptoms and preserved pancreatic exocrine function. Nonsurgical treatment with extracorporeal shock wave lithotripsy followed by endoscopic treatment if needed is useful as initial management for pancreatolithiasis.

Hemosuccus Pancreaticus: A Comprehensive Review of Presentation Patterns, Diagnostic Approaches, Therapeutic Strategies, and Clinical Outcomes

Hemosuccus pancreaticus is a rare but potentially torrential and life-threatening cause of acute upper gastrointestinal bleeding. It is described as an intermittent hemorrhage from the major duodenal papilla via the main pancreatic duct. Peripancreatic pseudoaneurysm following chronic pancreatitis is a common underlying etiology. However, gastroduodenal artery pseudoaneurysm-related hemosuccus pancreaticus remains exceedingly rare in the etiological spectrum of upper gastrointestinal bleeding. We hereby delineate a rare case of hemosuccus pancreaticus associated with gastroduodenal artery pseudoaneurysm in a patient who initially presented with abdominal pain and hematochezia. He was successfully managed with coil embolization without recurrence or sequelae. Furthermore, we conducted a search of the MEDLINE (PubMed and Ovid) database for relevant studies on hemosuccus pancreaticus published between inception and September 15, 2021. The available clinical evidence on causes, presentation patterns, diagnosis, and management was analyzed and summarized. This article highlights the rarity, the intermittent nature of hemorrhage, and the lack of a standardized diagnostic approach for this elusive disease. Clinicians should remain cognizant of hemosuccus pancreaticus, especially in patients presenting with symptoms and signs of intermittent gastrointestinal bleeding and abdominal pain. Prompt diagnosis carries paramount importance in saving patients from repeat hospital admissions and disease-associated morbidity and mortality. Conventional angiography with coil embolization may constitute an effective treatment strategy.

New evidence for adult beta cell neogenesis

In this issue of Cell Stem Cell, Gribben et al. (2021), using improved lineage-tracing mice and longer chase times, have provided clear evidence of new islet cells forming from the pancreatic ducts in adult mice. Perhaps these data will finally put to rest the controversy over beta cell neogenesis in the adult.

Calcified pseudocyst: an uncommon presentation of chronic pancreatitis

Pseudocysts are localised fluid collections, usually developing as a complication of acute or chronic pancreatitis. Pancreatic ductal or parenchymal calcifications are commonly seen in routine radiological imaging, but calcification of pseudocyst is extremely rare. Calcified pseudocysts have been reported in literature as case reports, but a calcified pseudocyst in the lesser sac, without underlying pancreatic calcification, has not been reported. We report a case of a pancreatic pseudocyst with a calcified wall, requiring surgical excision and histological examination confirming the diagnosis.

Pancreatic Ductal Adenocarcinoma Concomitant with Main Duct Type Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Case Report

BACKGROUND Intraductal papillary mucinous neoplasm of the pancreas (IPMN) and pancreatic ductal adenocarcinoma (PDAC) often coexist in the same pancreas. Almost all IPMNs involving PDACs concomitant with IPMN have been shown to be branch duct type IPMNs (BD-IPMNs), and their histological subtypes are gastric type. Therefore, PDACs concomitant with main duct type IPMNs (MD-IPMNs) are considered to be rare. We herein report a rare case preoperatively diagnosed as being a PDAC concomitant with MD-IPMN on the basis of imaging findings and histological findings of pancreatic specimens endoscopically obtained from 2 lesions. CASE REPORT A 67-year-old man was referred to our hospital due to an enlarged pancreas. Using imaging studies, a solid mass was found in the pancreatic head and intraductal papillary masses in the dilated main pancreatic duct of the body and tail with a fistula in the duodenum. On the basis of histological results using specimens endoscopically obtained from each of the 2 lesions, total pancreatectomy was planned due to suspected PDAC concomitant with an MD-IPMN. Finally, resected specimens were used to confirm the presence of a rare case of PDAC concomitant with MD-IPMN. CONCLUSIONS We encountered a rare case of a PDAC concomitant with an MD-IPMN which could be preoperatively diagnosed by using imaging studies and histological specimens endoscopically obtained. In addition to invasive cancers derived from IPMNs, PDACs concomitant with IPMNs can rarely develop in the pancreas involving MD-IPMNs.