Technical review of endoscopic ultrasound-guided drainage/anastomosis and trans-endosonographically created route procedures for the treatment of pancreatic diseases.

Endoscopic ultrasound (EUS)-guided pancreatic duct drainage includes two procedures: EUS-guided drainage/anastomosis (EUS-D/A) and trans-papillary drainage with EUS-assisted pancreatic rendezvous. EUS-guided pancreatogastrostomy is the most common EUS-D/A procedure and is recommended as a salvage procedure in cases in which endoscopic retrograde cholangiopancreatography fails or is difficult. However, initial EUS-D/A is performed in patients with surgically altered anatomy at our institution. It is one of the most difficult interventional EUS procedures and has a high incidence of adverse events. The technical difficulties differ according to etiology, and the incidence of adverse events varies between initial EUS-D/A and subsequent trans-endosonographically/EUS-guided created route procedures. Hence, it is important to meticulously prepare a procedure based on the patient's condition and the available devices. The technical difficulties in EUS-D/A include: (1) determination of the puncture point, (2) selection of a puncture needle and guidewire, (3) guidewire manipulation, and (4) dilation of the puncture route and stenting. Proper technical procedures are important to increase the success rate and reduce the incidence and severity of adverse events. The complexity of EUS-D/A is also contingent on the severity of pancreatic fibrosis and stricture. In post-pancreatectomy cases, determination of the puncture site is important for success because of the remnant pancreas. Trans-endosonographically/EUS-guided created route procedures following initial EUS-D/A are also important for achieving the treatment goal. This article focuses on effective strategies for initial EUS-D/A, based on the etiology and condition of the pancreas. We mainly discuss EUS-D/A, including its indications, techniques, and success-enhancing strategies.

TOKYO criteria 2024 for the assessment of clinical outcomes of endoscopic biliary drainage.

The consensus-based TOKYO criteria were proposed as a standardized reporting system for endoscopic transpapillary biliary drainage. The primary objective was to address issues arising from the inconsistent reporting of stent outcomes across studies, which has complicated the comparability and interpretation of study results. However, the original TOKYO criteria were not readily applicable to recent modalities of endoscopic biliary drainage such as biliary drainage based on endoscopic ultrasound or device-assisted endoscopy. There are increasing opportunities for managing hilar biliary obstruction and benign biliary strictures through endoscopic drainage. Biliary ablation has been introduced to manage benign and malignant biliary strictures. In addition, the prolonged survival times of cancer patients have increased the importance of evaluating overall outcomes during the period requiring endoscopic biliary drainage rather than solely focusing on the patency of the initial stent. Recognizing these unmet needs, a committee has been established within the Japan Gastroenterological Endoscopy Society to revise the TOKYO criteria for current clinical practice. The revised criteria propose not only common reporting items for endoscopic biliary drainage overall, but also items specific to various conditions and interventions. The term "stent-demanding time" has been defined to encompass the entire duration of endoscopic biliary drainage, during which the overall stent-related outcomes are evaluated. The revised TOKYO criteria 2024 are expected to facilitate the design and reporting of clinical studies, providing a goal-oriented approach to the evaluation of endoscopic biliary drainage.

Dedicated Echoendoscope for Interventional Endoscopic Ultrasound: Comparison with a Conventional Echoendoscope.

Background/Objective: Interventional endoscopic ultrasound (I-EUS) is technically difficult and has risks of severe adverse events due to the scarcity of dedicated endoscopes and tools. A new EUS scope was developed for I-EUS and was modified to increase the puncture range, reduce the blind area, and overcome guidewire difficulties. We evaluated the usefulness and safety of a new EUS scope compared to a conventional EUS scope. Methods: All I-EUS procedures were performed at Juntendo University Hospital from April 2020 to April 2022. The primary outcomes included the procedure time and fluoroscopy time. The secondary outcomes included the technical success rate and the rates of procedure-related adverse events. Clinical data were retrospectively reviewed and statistically analyzed between the new and conventional EUS scopes. Results: In total, 143 procedures in 120 patients were analyzed. The procedure time was significantly shorter with the new EUS scope, but the fluoroscopy time was not different. Among the patients only undergoing EUS-guided biliary drainage (EUS-BD), 79 procedures in 74 patients were analyzed. Both the procedure time and fluoroscopy time were significantly shorter with the new EUS scope. Multivariate analysis revealed that a new EUS scope and use of covered metal stents could reduce the fluoroscopy time. The technical success rate and the adverse event rate were not significantly different between the total I-EUS and the EUS-BD only groups. However, the conventional scope showed stent deviation during stent placement, which did not happen with the new scope. Conclusions: The new EUS scope reduced procedure time for total I-EUS and fluoroscopy time for EUS-BD compared to a conventional EUS scope because of the improvement suitable for I-EUS.

Endoscopic nasobiliary drainage versus endoscopic biliary stenting for preoperative biliary drainage in patients with malignant hilar biliary obstruction: Propensity score-matched multicenter comparative study.

OBJECTIVES: For preoperative biliary drainage (PBD) of malignant hilar biliary obstruction (MHBO), current guidelines recommend endoscopic nasobiliary drainage (ENBD) due to the higher risk of cholangitis after endoscopic biliary stenting (EBS) during the waiting period before surgery. However, few studies have supported this finding. Therefore, we aimed to compare the outcomes of preoperative ENBD and EBS in patients with MHBO. METHODS: Patients with MHBO who underwent laparotomy for radical surgery after ENBD or EBS were included from retrospectively collected data from 13 centers (January 2014 to December 2018). We performed a 1:1 propensity score matching between the ENBD and EBS groups. These patients were compared for the following: cholangitis and all adverse events (AEs) after endoscopic biliary drainage (EBD) until surgery, time to cholangitis development after EBD, postsurgical AEs, and in-hospital death after surgery. RESULTS: Of the 414 patients identified, 355 were analyzed in this study (226 for ENBD and 129 for EBS). The matched cohort included 63 patients from each group. The proportion of cholangitis after EBD was similar between the two groups (20.6% vs. 25.4%, P = 0.67), and no significant difference was observed in the time to cholangitis development. The proportions of surgical site infections, bile leaks, and in-hospital mortality rates were similar between the groups. CONCLUSION: For PBD of MHBO, the proportion of AEs, including cholangitis, after EBD until surgery was similar when either ENBD or EBS was used.

Current Situation and Problems in Diagnosis of Early Chronic Pancreatitis.

OBJECTIVES: The Japan Pancreas Society introduced the concept of early chronic pancreatitis (ECP) in 2009, but its epidemiology remains unclear. This study investigated challenges in ECP diagnosis. METHODS: Early chronic pancreatitis was diagnosed in 4 cohorts between April 2019 and November 2021 using the Clinical Diagnostic Criteria for Chronic Pancreatitis 2019. These cohorts included patients with abdominal/back pain, abnormal pancreatic enzyme levels, ECP suspected due to other reasons, and those who underwent endoscopic ultrasonography for other diseases. RESULTS: A total of 2502 cases were analyzed and 150 (40 alcoholic and 110 nonalcoholic) cases with ECP findings on endoscopic ultrasonography were included. Early chronic pancreatitis was confirmed in 14 cases (9%), including 9 (22.5%) alcoholic and 5 (4.5%) nonalcoholic cases. Early chronic pancreatitis was confirmed in 15%, 0%, 2.2%, and 0.13% cases in the 4 cohorts, respectively. Early chronic pancreatitis was confirmed in 10 (48%) of the 21 (14%) cases with pancreatic pain. CONCLUSIONS: Early chronic pancreatitis diagnostic rate was low, particularly in nonalcoholic cases, but was slightly higher in cases with pancreatic pain. The diagnostic rate was highest in the abdominal/back pain group. Further studies are required to establish appropriate diagnostic criteria for ECP.

Risk factors for adverse outcomes at various phases of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Data from a multi-institutional consortium.

OBJECTIVES: No comprehensive study has examined short- and long-term adverse outcomes of endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs) including walled-off necrosis (WON) and pseudocysts. METHODS: In a multi-institutional cohort of 357 patients receiving EUS-guided treatment of PFCs (228 with WON and 129 with pseudocysts), we examined PFC type-specific risk factors for procedure-related adverse events (AEs), clinical failure, and recurrence. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the logistic and Cox regression models, respectively, adjusting for potential confounders. RESULTS: Adverse events were observed predominantly in WON, and risk factors were WON extension to the pelvis (OR 2.49; 95% CI 1.00-6.19) and endoscopic necrosectomy (OR 5.15; 95% CI 1.61-16.5). Risk factors for clinical failure in WON treatment included higher Charlson Comorbidity Index (OR for ≥3 vs. ≤2, 2.58; 95% CI 1.05-6.35), extension to the pelvis (OR 3.63; 95% CI 1.57-8.43), nonuse of a lumen-apposing metal stent (OR 2.88; 95% CI 1.10-7.54), and percutaneous drainage (OR 3.73; 95% CI 1.27-10.9). Patients with pseudocysts extending to the paracolic gutter and the need for more than two endoscopic/percutaneous procedures had ORs for clinical failure of 5.28 (95% CI 1.10-25.3) and 5.52 (95% CI 1.61-18.9), respectively. Pseudocysts requiring the multigateway approach were associated with a high risk of recurrence (HR 4.00; 95% CI 1.11-11.6). CONCLUSION: The adverse outcomes at various phases of EUS-guided PFC treatment may be predictable based on clinical parameters. Further research is warranted to optimize treatment strategies for high-risk patients.

WONDER-01: immediate necrosectomy vs. drainage-oriented step-up approach after endoscopic ultrasound-guided drainage of walled-off necrosis-study protocol for a multicentre randomised controlled trial.

BACKGROUND: With the increasing popularity of endoscopic ultrasound (EUS)-guided transmural interventions, walled-off necrosis (WON) of the pancreas is increasingly managed via non-surgical endoscopic interventions. However, there has been an ongoing debate over the appropriate treatment strategy following the initial EUS-guided drainage. Direct endoscopic necrosectomy (DEN) removes intracavity necrotic tissue, potentially facilitating early resolution of the WON, but may associate with a high rate of adverse events. Given the increasing safety of DEN, we hypothesised that immediate DEN following EUS-guided drainage of WON might shorten the time to WON resolution compared to the drainage-oriented step-up approach. METHODS: The WONDER-01 trial is a multicentre, open-label, superiority, randomised controlled trial, which will enrol WON patients aged ≥ 18 years requiring EUS-guided treatment in 23 centres in Japan. This trial plans to enrol 70 patients who will be randomised at a 1:1 ratio to receive either the immediate DEN or drainage-oriented step-up approach (35 patients per arm). In the immediate DEN group, DEN will be initiated during (or within 72 h of) the EUS-guided drainage session. In the step-up approach group, drainage-based step-up treatment with on-demand DEN will be considered after 72-96 h observation. The primary endpoint is time to clinical success, which is defined as a decrease in a WON size to ≤ 3 cm and an improvement of inflammatory markers (i.e. body temperature, white blood cell count, and C-reactive protein). Secondary endpoints include technical success, adverse events including mortality, and recurrence of the WON. DISCUSSION: The WONDER-01 trial will investigate the efficacy and safety of immediate DEN compared to the step-up approach for WON patients receiving EUS-guided treatment. The findings will help us to establish new treatment standards for patients with symptomatic WON. TRIAL REGISTRATION: ClinicalTrials.gov NCT05451901, registered on 11 July 2022. UMIN000048310, registered on 7 July 2022. jRCT1032220055, registered on 1 May 2022.

A pilot study of Spring Stopper Stents: Novel partially covered self-expandable metallic stents with anti-migration properties for EUS-guided hepaticogastrostomy.

Background and Objectives: EUS-guided hepaticogastrostomy (EUS-HGS) is an effective salvage procedure when conventional endoscopic transpapillary biliary drainage is difficult or fails. However, the risk of stent migration into the abdominal cavity has not been resolved completely. In this study, we evaluated a newly developed partially covered self-expandable metallic stent (PC-SEMS) that has a spring-like anchoring function on the gastric side. Methods: This retrospective pilot study took place at four referral centers in Japan between October 2019 and November 2020. We enrolled 37 cases consecutively who underwent EUS-HGS for unresectable malignant biliary obstruction. Results: The rates of technical and clinical success were 97.3% and 89.2%, respectively. Technical failures included one case in which the stent was dislocated during the removal of the delivery system, requiring additional EUS-HGS on another branch. Early adverse events (AEs) were observed in four patients (10.8%): two with mild peritonitis (5.4%) and one each (2.7%) with fever and bleeding. No late AEs were observed during the mean follow-up period of 5.1 months. All recurrent biliary obstructions (RBOs) were stent occlusions (29.7%). The median cumulative time to RBO was 7.1 months (95% confidence interval, 4.3 to not available). Although stent migration in which the stopper was in contact with the gastric wall on follow-up computed tomography was observed in six patients (16.2%), no migration was observed. Conclusions: The newly developed PC-SEMS is feasible and safe for the EUS-HGS procedure. The spring-like anchoring function on the gastric side is an effective anchor preventing migration.

A follow-up questionnaire survey 2022 on radiation protection among 464 medical staff from 34 endoscopy-fluoroscopy departments in Japan.

Objectives: We surveyed and reported low protective equipment usage and insufficient knowledge among endoscopy-fluoroscopy departments in Japan in 2020. Two years later, we conducted a follow-up survey of doctors, nurses, and technologists in Japan. Methods: We conducted a questionnaire survey on radiation protection from May to June 2022. The participants were medical staff, including doctors, nurses, and radiological and endoscopy technicians in endoscopy-fluoroscopy departments. The questionnaire included 17 multiple-choice questions divided into three parts: background, equipment, and knowledge. Results: We surveyed 464 subjects from 34 institutions. There were 267 doctors (58%), 153 nurses (33%), and 44 technologists (9%). The rate of wearing a lead apron was 98% in this study. The rates of wearing a thyroid collar, lead glasses, and radiation dosimeter were 27%, 35%, and 74%, respectively. The trend of the protective equipment rate was similar to that of our previous study; however, radiation dosimetry among doctors was still low at 58%. The percentage of subjects who knew the radiation exposure (REX) dose of each procedure was low at 18%. Seventy-six percent of the subjects attended lectures on radiation protection, and 73% knew about the three principles of radiation protection; however, the concept of diagnostic reference levels was not well known (18%). Approximately 60% of the subjects knew about the exposure dose increasing cancer mortality (63%) and the 5-year lens REX limit (56%). Conclusions: There was some improvement in radiation protection equipment or education, but relatively little compared to the 2020 survey of endoscopy departments.

Evaluation of the mechanical properties of current biliary self-expandable metallic stents: axial and radial force, and axial force zero border.

BACKGROUND/AIMS: Mechanical properties (MPs) and axial and radial force (AF and RF) may influence the efficacy and complications of self-expandable metallic stent (SEMS) placement. We measured the MPs of various SEMSs and examined their influence on the SEMS clinical ability. METHODS: We evaluated the MPs of 29 types of 10-mm SEMSs. RF was measured using a conventional measurement device. AF was measured using the conventional and new methods, and the correlation between the methods was evaluated. RESULTS: A high correlation in AFs was observed, as measured by the new and conventional manual methods. AF and RF scatterplots divided the SEMSs into three subgroups according to structure: hook-and-cross-type (low AF and RF), cross-type (high AF and low RF), and laser-cut-type (intermediate AF and high RF). The hook-and-cross-type had the largest axial force zero border (>20°), followed by the laser-cut and cross types. CONCLUSION: MPs were related to stent structure. Hook-and-cross-type SEMSs had a low AF and high axial force zero border and were considered safest because they caused minimal stress on the biliary wall. However, the increase in RF must be overcome.

Measurement of the anchoring force of covered self-expandable and lumen-apposing metal stents for interventional endoscopic ultrasonography.

OBJECTIVES: Interventional endoscopic ultrasonography is performed for various situations that require drainage, after which stent migration is the most severe adverse event. Several lumen-apposing metal stents (LAMS) and covered self-expandable metal stents (CSEMS) provide antimigration systems; however, their anchoring ability has not been studied well. Therefore, we measured and compared the anchoring force (ACF) of commercially available LAMS and CSEMS. METHODS: Anchoring force was measured for five types of LAMS (NAGI, SPAXUS, Plumber, and AXIOS 8 and 10 mm) and seven types of CSEMS (BCL, SHCL, BCG, BPD [four types of HANAROSTENT], HILZO, Niti-S [Spring Stopper], and Wallflex). We created a phantom model for inducing stent migration. It has a rotatable part as a curved fixture, and we measured ACF at angles between 0° and 40°. RESULTS: The mean ACF at 0° and 20° were NAGI 1.50, 1.84 N, SPAXUS 1.73, 1.72 N, Plumber 2.64, 2.03 N, and AXIOS 3.96, 3.61 N, respectively; and BCL 0.48, 0.53 N, Wallflex 0.53, 0.48 N, SHCL 0.64, 0.73 N, HILZO 1.09, 1.09 N, BCG 1.22, 1.20 N, BPD 1.78, 1.67 N, and Spring Stopper 2.29, 2.51 N. CONCLUSION: We measured ACF in LAMS and CSEMS with a new phantom model. The highest value among the LAMS was for the AXIOS and among the CSEMS was for the Spring Stopper. Some of the ACF values varied with the direction of pull. These findings may have a significant impact on stent selection for interventional endoscopic ultrasonography, and this model can be used to evaluate newly developed stents.

A case of groove pancreatitis with duodenal stenosis successfully treated by endoscopic ultrasonography-guided pancreaticogastrostomy.

One of the reasons for groove pancreatitis is caused by the leakage of pancreatic juice into the space between the pancreatic head, descending duodenum, and common bile duct. Endoscopic drainage of Santorini's duct (SD) via the minor papilla is reportedly efficacious but can be difficult due to duodenal stenosis. We report Santorini's duct drainage using endoscopic ultrasonography-guided pancreaticogastrostomy (EUS-PGS) for a case of groove pancreatitis with gastric outlet obstruction. Gastric outlet obstruction was improved after 7 months of EUS-PGS with internal drainage through the Santorini's duct/minor papilla. EUS-PGS may be effective for treating groove pancreatitis with duodenal stenosis. This is the first report of groove pancreatitis with duodenal stenosis, the symptoms of which were improved by EUS-PGS.

STNM01, the RNA oligonucleotide targeting carbohydrate sulfotransferase 15, as second-line therapy for chemotherapy-refractory patients with unresectable pancreatic cancer: An open label, phase I/IIa trial.

Background: The impact of stroma-targeting therapy on tumor immune suppression is largely unexplored. An RNA oligonucleotide, STNM01, has been shown to repress carbohydrate sulfotransferase 15 (CHST15) responsible for tumor proteoglycan synthesis and matrix remodeling. This phase I/IIa study aimed to evaluate the safety and efficacy of STNM01 in patients with unresectable pancreatic ductal adenocarcinoma (PDAC). Methods: This was an open-label, dose-escalation study of STNM01 as second-line therapy in gemcitabine plus nab-paclitaxel-refractory PDAC. A cycle comprised three 2-weekly endoscopic ultrasound-guided locoregional injections of STNM01 at doses of 250, 1,000, 2,500, or 10,000 nM in combination with S-1 (80-120 mg twice a day for 14 days every 3 weeks). The primary outcome was the incidence of dose-liming toxicity (DLT). The secondary outcomes included overall survival (OS), tumor response, changes in tumor microenvironment on immunohistopathology, and safety (jRCT2031190055). Findings: A total of 22 patients were enrolled, and 3 cycles were repeated at maximum; no DLT was observed. The median OS was 7.8 months. The disease control rate was 77.3%; 1 patient showed complete disappearance of visible lesions in the pancreas and tumor-draining lymph nodes. Higher tumoral CHST15 expression was associated with poor CD3+ and CD8+ T cell infiltration at baseline. STNM01 led to a significant reduction in CHST15, and increased tumor-infiltrating CD3+ and CD8+ T cells in combination with S-1 at the end of cycle 1. Higher fold increase in CD3+ T cells correlated with longer OS. There were 8 grade 3 adverse events. Interpretation: Locoregional injection of STNM01 was well tolerated in patients with unresectable PDAC as combined second-line therapy. It prolonged survival by enhancing T cell infiltration in tumor microenvironment. Funding: The present study was supported by the Japan Agency for Medical Research and Development (AMED).

Clinical Outcomes of Inside Stents and Conventional Plastic Stents as Bridge-to-Surgery Options for Malignant Hilar Biliary Obstruction.

BACKGROUND: The appropriate method of preoperative endoscopic biliary drainage (EBD) for cholangiocarcinoma with hilar biliary obstruction remains controversial. The inside-stent technique is a method of placing plastic stents entirely inside the bile duct. Several studies of patients with unresectable stage have reported longer stent patency compared with conventional endoscopic biliary stenting (EBS). Inside-stent techniques have been introduced as a bridge-to-surgery option and as an alternative to conventional EBS. AIMS: We aimed to evaluate the clinical outcomes of inside stent use and conventional EBS. METHODS: During this retrospective multicenter study, we reviewed consecutive patients with cholangiocarcinoma who underwent radical surgery after conventional EBS or inside-stent insertion. Adverse event (AE) rates after EBD and post-surgical AEs were compared. A multivariable analysis was performed to identify factors affecting cholangitis after EBD. RESULTS: Conventional EBS and inside-stent procedures were performed for 56 and 73 patients, respectively. Patient backgrounds were similar between groups, except for percutaneous transhepatic portal vein embolization. The waiting time before surgery was similar between groups (28.5 days vs. 30 days). There were no significant differences in the cholangitis rate (21.4% vs. 26.0%; P = 0.68) and all AEs (25.0% vs. 30.1%; P = 0.56) between groups. The post-surgical AE rate was similar between the groups. The multivariable analysis found that preprocedural cholangitis was a risk factor for cholangitis after EBD (odds ratio: 5.67; 95% confidence interval: 1.61-19.9). CONCLUSIONS: The outcomes of inside-stent techniques and conventional EBS for the management of preoperative EBD are comparable for patients with cholangiocarcinoma.