Objectives: Pancreatic duct (PD) brush cytology (BC) and fluorescence in-situ hybridization (FISH) are viable techniques but underutilized due to limited data on their diagnostic accuracy for pancreatic malignancy and associated risks. This study evaluates the safety and diagnostic performance of BC, FISH, and their combination for detecting pancreatic malignancy. Methods: A retrospective analysis was conducted on subjects undergoing endoscopic retrograde cholangiopancreatography (ERCP) PD brushings at a tertiary hospital. Data included demographics, procedural details, adverse events, and outcomes. Malignancy was confirmed by EUS-guided biopsy or surgical histology. Diagnostic metrics for BC, FISH, and their combination were calculated. Results: Of the 205 subjects who underwent ERCP PD brushings from 2004 to 2023, 35 (17.1%) were diagnosed with pancreatic malignancy. BC had a sensitivity of 31.4% and specificity of 95.9% (AUC 0.64). Abnormal FISH showed 45.7% sensitivity and 89.4% specificity (AUC 0.68), while polysomy FISH had 28.6% sensitivity and 97.1% specificity (AUC 0.63). Combined BC and abnormal FISH yielded 54.3% sensitivity and 87.7% specificity (AUC 0.71). AEs included post-ERCP pancreatitis in 16 cases (7.8%), bleeding in 2 (1.0%), and micro-perforation in 1 (0.5%). Conclusions: PD brushing for BC and FISH is generally safe with modest diagnostic accuracy for malignancy. While novel diagnostic tests such as molecular biomarkers in pancreatic fluid for detecting PC are still needed, PD brushings can assist in the detection of PC with low rates of PEP in select subjects.

Background: Self-expanding metal stents (SEMS) are recommended for the endoscopic palliation of distal malignant biliary obstruction (DMBO). Placement of SEMS during endoscopic retrograde cholangiopancreatography (ERCP) has been associated with an increased risk of post-ERCP pancreatitis (PEP). Objectives: The aim of this study is to evaluate rates of PEP in patients who underwent SEMS placement for pancreatic versus non-pancreatic malignancy. Design: Retrospective Cohort Study. Methods: Patients who underwent SEMS placement for DMBO between June 2017 and May 2021 were identified retrospectively from a procedural billing database. PEP incidence was compared between pancreatic and non-pancreatic DMBO groups and multivariate logistic regression was performed to identify risk factors for PEP. Results: A total of 488 individuals were identified, with 395 (80.9%) cases of DMBO due to pancreatic and 93 (19.1%) due to non-pancreatic malignancy. Stent types included 124 (25.4%) fully covered (FCSEMS) and 364 (74.6%) uncovered metal stents (UCSEMS). The overall rate of PEP in the cohort was 6.3% with no significant difference between pancreatic and non-pancreatic etiologies (6.1% vs 7.5%, p = 0.606). When adjusted for age <50 years old, female sex, and pancreatic stent placement, a non-pancreatic malignancy was not associated with an increased risk of PEP (OR 0.83, 95% CI 0.36–2.15). Conclusion: No statistically significant difference in PEP rates was seen after biliary sphincterotomy and SEMS placement for palliation of DMBO in patients with pancreatic versus non-pancreatic malignancies.

BACKGROUND AND AIMS:Endoscopic palliation of obstructive jaundice from distal malignant biliary obstruction (dMBO) improves the quality of life of patients. This study aims to compare the clinical outcomes at 6 months after implantation of traditional fully covered self-expandable metal stents (FCSEMSs) versus those with antimigration fins (FCSEMS-AF) in patients with dMBO. METHODS:Individuals undergoing FCSEMS or FCSEMS-AF placement for dMBO from May 2017 to September 2023 were identified. Outcomes included intervention-free stent patency, reintervention rates, time to endoscopic reintervention, clinical success, and adverse events (AEs). Analysis included Kaplan-Meier curves and Cox proportional hazards models. RESULTS:The cohort included 215 patients (142 with FCSEMSs and 73 with FCSEMSs-AF). Clinical success was similar in both groups (93.7% in FCSEMSs vs 95.9% in FCSEMSs-AF; P = .500). At 6 months, 84.8% of FCSEMSs had intervention-free patency compared to 77.1% of FCSEMSs-AF (P = .461), with similar rates of AEs (16.2% in FCSEMS and 21.7% in FCSEMS-AF groups; P = .335) and reintervention (16.2% of FCSEMSs and 22.1% of FCSEMSs-AF; P = .324). At 6 months, FCSEMSs-AF had higher rates of stent occlusion (13.2% of FCSEMSs vs 28.3% of FCSEMSs-AF; P = .011) and lower rates of migration (7.6% of FCSEMSs vs 0% of FCSEMSs-AF; P = .011). After adjusting for stent length, FCSEMSs had a higher risk of migration (hazard ratio 12.23 [95% CI, 1.9-78.66]; P = .008) with similar occlusion risk (hazard ratio 0.68 [95% CI, 0.31-1.51]; P = .342). CONCLUSIONS:FCSEMSs and FCSEMSs-AF have similar performance characteristics at 6 months; however FCSEMSs were more likely to migrate and had similar occlusion risk after stent length adjustment. These findings can provide insight into the current limitations and help guide future stent design.

Background Clinicians struggle to accurately classify biliary strictures as benign or malignant. Current endoscopic retrograde cholangiopancreatography (ERCP)-based sampling modalities including brush cytology and forceps biopsy have poor sensitivity for pathologic confirmation of malignancy. Cholangioscopy allows for direct visualization and sampling of biliary pathology; however, this technology is also associated with inaccurate classification of biliary disease. Previously, an artificial intelligence (AI) system that analyzes cholangioscopy footage was found to be more accurate in diagnosing biliary malignancy than ERCP sampling techniques. The aim of this study was to validate this AI system on a new series of examinations. Method Three academic centers collected all available unedited cholangioscopy recordings. The videos were processed by the cholangioscopy AI system. After analyzing videos, the AI system provided predictions as to whether malignancy was present. AI performance in classifying strictures was compared with the performance of brush cytology and forceps biopsy. Results 112 cholangioscopy examinations (containing 4 817 081 images) were generated from 99 patients. Of those examinations, 61 (54.5%) were for investigation of biliary strictures (31 [50.8%] benign, 30 [49.2%] malignant). For the correct classification of strictures, the AI system was 80.0% sensitive and 90.3% specific. It was also significantly more accurate for stricture classification (85.2%) than brush cytology (52.5%; P<0.001), forceps biopsy (68.2%; P=0.04), and the combination of brush cytology and forceps biopsy (66.7%; P=0.02). Conclusion A previously developed cholangioscopy AI system was found to continually outperform standard ERCP sampling modalities for accurate identification of malignancy, without additional retraining, in a multicenter validation cohort.

Background and Aims: Peroral cholangiopancreatoscopy (POCP) is increasingly used in complex ERCP but remains limited by small working channels and maneuverability challenges. This case series describes early user experience with a novel single-use POCP system for evaluation of indeterminate biliary strictures and electrohydraulic lithotripsy (EHL) of pancreatic and biliary stones. Methods: A case series included individuals undergoing evaluation for indeterminate biliary strictures and complex stone management. Procedures were evaluated for technical success, usability (Likert scale), diagnostic yield, and adverse events (AEs). Results: Twelve patients were included. Among the 9 who underwent cholangioscopy-directed biopsy samples, all provided adequate tissue. Of 6 malignancies, none were diagnosed by brush cytology, whereas cholangioscopy-directed biopsy samples were diagnostic in 4 of 5 cases of cholangiocarcinoma and 1 case of hepatocellular carcinoma. In all 3 stone cases, a 4.5F (catheter/probe size unit; 1F = 0.33 mm) EHL probe was successfully advanced, achieving complete stone clearance in a single session. Five endoscopists performed the procedures, reporting high Likert scores for pushability, tip control, device passage, and image quality. No periprocedural AEs were noted. Conclusions: In this limited single-center, noncomparative experience, the system enabled tissue sampling and EHL with reported ease of use. These preliminary findings should be interpreted cautiously and in the context of standard ERCP risks, including pancreatitis, infection, perforation, and cholangitis.

Patients with a history of Metabolic and Bariatric Surgery (MBS) face an increased risk of acute pancreatitis (AP) due to factors like rapid weight loss and altered gastrointestinal anatomy. However, data on the severity and outcomes of AP in these patients are limited. This study evaluates whether a history of MBS, particularly Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion with duodenal switch (BPD/DS), affects the severity and clinical outcomes of AP. This retrospective matched cohort study included patients admitted with AP to Mayo Clinic between 2013 and 2022. Patients with a history of RYGB or BPD/DS were matched to two control groups without prior bariatric surgery: (1) BMI-matched controls (± 1 kg/m2), and (2) higher-BMI controls (≥ 5 kg/m2 higher). The primary outcome was AP severity, and secondary outcomes included local complications, hospital length of stay, recurrence, and 30-day readmission. Compared to the higher-BMI control group, the MBS group had lower rates of severe AP (0

BACKGROUND:Fluorescence in situ hybridization (FISH) is recommended as part of multimodality sampling in the evaluation of biliary strictures, but can be false negative in 40%-50% cases. The aim of this study was to comprehensively assess predictors of false-negative FISH in patients with biliary strictures. METHODS:Patients undergoing tissue sampling for biliary strictures from October 20 to February 22 were prospectively enrolled (NCT04572711). Procedural factors such as sampling techniques, order, and utilization of combination sampling were recorded. Results of an optimized pancreatobiliary FISH panel with locus-specific probes for 1q21, 7p12, 8q24, and 9p21 were reported per guidelines. Statistical analyses were performed using BlueSky Statistics v.10.3.1, R package v8.81. RESULTS:Of 327 patients, 93 (28.5%) were diagnosed with malignancy. A false-negative pancreatobiliary fluorescence in situ hybridization (PB-FISH) was reported in 40 (43.1%) patients. A history of primary sclerosing cholangitis was associated with lower odds of having a false-negative PB-FISH (aOR=0.38, 95% CI=0.16-0.82, p=0.02), whereas a hilar stricture was associated with a significantly higher false-negative PB-FISH in those with cholangiocarcinoma (aOR=3.2 [1.4-7.9], p=0.009). Dilation of biliary strictures prior to brushing was not associated with a lower rate of false-negative PB-FISH. CONCLUSIONS:In this prospective study, hilar strictures were more likely to have false-negative PB-FISH. Dilation of strictures did not affect PB-FISH performance. These results can help guide PB-FISH interpretation.

Background and Aims Difficult biliary cannulation (DBC) is a known risk factor for developing post-ERCP pancreatitis (PEP). To better understand how DBC increases PEP risk, we examined the interplay between technical aspects of DBC and known PEP risk factors. Methods This was a secondary analysis of a multicenter, randomized controlled trial comparing rectal indomethacin alone with the combination of rectal indomethacin and prophylactic pancreatic duct (PD) stent placement for PEP prophylaxis in high-risk patients. Participants were categorized into 3 groups: DBC with high preprocedure risk for PEP, DBC without high preprocedure risk for PEP, and non-DBC at high preprocedure risk for PEP. Results In all, 1601 participants (84.1%) experienced DBC, which required a mean of 12 cannulation attempts (standard deviation, 10) and mean duration of 14.7 minutes (standard deviation, 14.9). PEP rate was highest (20.7%) in DBC with a high preprocedure risk, followed by non-DBC with a high preprocedure risk (13.5%), and then DBC without a high preprocedure risk (8.8%). Increasing number of PD wire passages (adjusted odds ratio [aOR], 1.97; 95% confidence interval [CI], 1.25-3.1) was associated with PEP in DBC, but PD injection, pancreatic sphincterotomy, and number of cannulation attempts were not associated with PEP. Combining indomethacin with PD stent placement lowered the risk of PEP (aOR, .61; 95% CI, .44-.84) in DBCs. This protective effect was evident in up to at least 4 PD wire passages. Conclusions DBC confers higher PEP risk in an additive fashion to preprocedural risk factors. PD wire passages appear to add the greatest PEP risk in DBCs, but combining indomethacin with PD stent placement reduces this risk, even with increasing PD wire passages.

BACKGROUND AND AIMS:Pancreatic fluid collections (PFCs) may recur after initial successful endoscopic drainage of walled-off necrosis (WON), most commonly due to disconnected pancreatic duct syndrome (DPDS). The primary aim of this study was to assess the role of MRCP for identifying DPDS to guide appropriate management and prevent PFC recurrence. METHODS:Patients with WON undergoing lumen-apposing metal stent drainage of a PFC were retrospectively identified and categorized as those with MRCP versus those without MRCP before removal of transmural stents. Data on patient demographic characteristics, procedural details, cross-sectional imaging, and recurrence rates were collected through chart review. RESULTS:A total of 121 patients with WON were identified, of whom 44 (36.4%) had an MRCP before transmural stent removal. In patients without MRCP, 13 (16.8%) of 77 had PFC recurrence versus 0 of 44 (0%; P = .003) in those with MRCP. MRCP identified DPDS in 12 (27.2%) patients, all of whom were managed with indefinite drainage with double-pigtail plastic stents without recurrence. In the group without MRCP, PFCs recurred at a median interval of 284 days (interquartile range, 182-618 days) after transmural stent removal. Among the 13 patients with PFC recurrence, 11 (85%) had undiagnosed DPDS detected on subsequent imaging, of whom 9 were subsequently managed with indefinite double-pigtail plastic stents, with no further PFC recurrence. CONCLUSIONS:Patients with WON who underwent MRCP before transmural stent removal had a lower rate of PFC recurrence largely due to the identification of DPDS with appropriate endoscopic management.

BACKGROUND:The authors previously developed an artificial intelligence (AI) to assist cytologists in the evaluation of digital whole-slide images (WSIs) generated from bile duct brushing specimens. The aim of this trial was to assess the efficiency and accuracy of cytologists using a novel application with this AI tool. METHODS:Consecutive bile duct brushing WSIs from indeterminate strictures were obtained. A multidisciplinary panel reviewed all relevant information and provided a central interpretation for each WSI as being "positive," "negative," or "indeterminate." The WSIs were then uploaded to the AI application. The AI scored each WSI as positive or negative for malignancy (i.e., computer-aided diagnosis [CADx]). For each WSI, the AI prioritized cytologic tiles by the likelihood that malignant material was present in the tile. Via the AI, blinded cytologists reviewed all WSIs and provided interpretations (i.e., computer-aided detection [CADe]). The diagnostic accuracies of the WSI evaluation via CADx, CADe, and the original clinical cytologic interpretation (official cytologic interpretation [OCI]) were compared. RESULTS:Of the 84 WSIs, 15 were positive, 42 were negative, and 27 were indeterminate after central review. The WSIs generated on average 141,950 tiles each. Cytologists using the AI evaluated 10.5 tiles per WSI before making an interpretation. Additionally, cytologists required an average of 84.1 s of total WSI evaluation. WSI interpretation accuracies for CADx (0.754; 95% CI, 0.622-0.859), CADe (0.807; 95% CI, 0.750-0.856), and OCI (0.807; 95% CI, 0.671-0.900) were similar. CONCLUSIONS:This trial demonstrates that an AI application allows cytologists to perform a triaged review of WSIs while maintaining accuracy.

Background/Aims: Coaxial placement of double pigtail plastic stents (DPPS) through lumen-apposing metal stents (LAMSs) is commonly performed to reduce the risk of LAMS obstruction, bleeding, and stent migration when used for the drainage of pancreatic fluid collections (PFCs). A systematic review and meta-analysis were performed to compare the outcomes of LAMS alone and LAMS with coaxial DPPS placement in the management of PFCs.Methods: A systematic review was conducted to identify studies comparing LAMS and LAMS/DPPS for PFC drainage. Primary outcomes included the rate of clinical success, overall adverse events (AEs), bleeding, infection, occlusion, and stent migration. The pooled effect size was summarized using a random-effects model and compared between LAMS and LAMS/DPPS by calculating odds ratios (ORs).Results: Nine studies involving 709 patients were identified (338 on LAMS and 371 on LAMS/DPPS). LAMS/DPPS was associated with a reduced risk of stent obstruction (OR, 0.59; p=0.004) and infection (OR, 0.55; p=0.001). No significant differences were observed in clinical success (OR, 0.96; p=0.440), overall AEs (OR, 0.57; p=0.060), bleeding (OR, 0.61; p=0.120), or stent migration (OR, 1.03; p=0.480).Conclusions: Coaxial DPPS for LAMS drainage of PFCs is associated with a reduced risk of stent occlusion and infection; however, no difference was observed in the overall AE rates or bleeding.