Safety and efficacy of low-power pure-cut hot snare polypectomy for small nonpedunculated colorectal polyps compared with conventional resection methods: A propensity score matching analysis.

Objectives: Cold snare polypectomy (CSP) is widely performed for small colorectal polyps. However, small colorectal polyps sometimes include high-grade adenomas or carcinomas that require endoscopic resection with electrocautery. This study aimed to evaluate the efficacy and safety of a novel resection technique, hot snare polypectomy with low-power pure-cut current (LPPC-HSP) for small colorectal polyps, compared with CSP and conventional endoscopic mucosal resection (EMR). Methods: Records of patients who underwent CSP, EMR, or LPPC-HSP for nonpedunculated colorectal polyps less than 10 mm between April 2021 and March 2022 were retrospectively evaluated. We analyzed and compared the treatment outcomes of CSP and EMR with those of LPPC-HSP using propensity score matching. Results: After propensity score matching of 396 pairs, an analysis of CSP and LPPC-HSP indicated that LPPC-HSP had a significantly higher R0 resection rate (84% vs. 68%; p < 0.01). Delayed bleeding was observed in only two cases treated with CSP before matching. Perforation was not observed with either treatment. After propensity score matching of 176 pairs, an analysis of EMR and LPPC-HSP indicated that their en bloc and R0 resection rates were not significantly different (99.4% vs. 100%, p = 1.00; 79% vs. 81%, p = 0.79). Delayed bleeding and perforation were not observed with either treatment. Conclusions: The safety of LPPC-HSP was comparable to that of CSP. The treatment outcomes of LPPC-HSP were comparable to those of conventional EMR for small polyps. These results suggest that this technique is a safe and effective treatment for nonpedunculated polyps less than 10 mm.

Low-power pure-cut hot snare polypectomy for colorectal polyps 10-14 mm in size: a multicenter retrospective study.

BACKGROUND AND AIM: Hot snare excision using electrocautery is widely used for large colorectal polyps (>10 mm); however, adverse events occur due to deep thermal injury. Colorectal polyps measuring 10-14 mm rarely include invasive cancer. Therefore, less invasive therapeutic options for this size category are demanding. We have developed hot snare polypectomy with low-power pure-cut current (LPPC HSP), which is expected to contribute to less deep thermal damage and lower risk of adverse events. This study aimed to evaluate the efficacy and safety of LPPC HSP for 10-14 mm colorectal polyps, compared with conventional endoscopic mucosal resection (EMR). METHODS: In this multicenter, retrospective, observational study, clinical outcomes of EMR and LPPC HSP for 10-14 mm nonpedunculated colorectal polyps between January 2021 and March 2022 were compared using propensity score matching. RESULTS: We identified 203 EMR and 208 LPPC HSP cases. After propensity score matching, the baseline characteristics between the groups were comparable, with 120 pairs. The en bloc and R0 resection rates were not significantly different between EMR and LPPC HSP groups (95.8% vs 97.5%, P = 0.72; 90.0% vs 91.7%, P = 0.82). The rates of delayed bleeding and perforation did not differ between the groups. CONCLUSIONS: Compared with conventional EMR, LPPC HSP showed a similar resection ability without an increase in adverse events. These results suggest that LPPC HSP is a safe and effective treatment for 10-14 mm nonpedunculated colorectal polyps.

FOXA1/CK7-positive Esophageal Squamous Cell Carcinoma with Aggressive Liver Metastasis: A Case Report.

Cytokeratin (CK) is a specific marker of adenocarcinoma. However, cases of CK7-positive esophageal squamous cell carcinoma (ESCC) have only rarely been reported. We herein report a case of unresectable CK7-positive ESCC with aggressive liver metastasis following nivolumab treatment initiation. Nivolumab treatment was discontinued after one course because of complications. Notably, the liver metastases exhibited accelerated growth. Immunostaining of the necropsy specimens revealed diffuse positivity for forkhead box protein A1 (FOXA1)/CK7, thus indicating a potent poor immune response. The potential correlation between CK7 expression and the immune checkpoint inhibitor response may offer valuable insights into the development of effective therapeutic strategies.

Gel immersion endoscopic mucosal resection for early gastric neoplasms: a multicenter case series study.

Several cases have been reported that suggest the efficacy of gel immersion endoscopic mucosal resection (GI-EMR) for gastric neoplasms. However, no study has evaluated treatment outcomes of GI-EMR for gastric neoplasms. This study aimed to investigate the efficacy and safety of GI-EMR for early gastric neoplasms. Nine patients (17 lesions) undergoing gastric GI-EMR were included, with a median lesion size of 10 mm (interquartile range [IQR] 5-13 mm). All lesions were protruding or flat elevated. The median procedure time was 3 minutes (IQR 2-5) and en bloc resection was achieved in all cases. Among 15 neoplastic lesions, the R0 resection rate was 86.7% (13/15 lesions). Adverse events included immediate bleeding requiring hemostasis in two cases, which was controlled endoscopically. No delayed bleeding or perforation occurred. In conclusion, GI-EMR may be a safe and effective treatment for early, small gastric neoplasms. However, due to the small sample in the present study, further investigation is required regarding the indication for this technique.

Adverse events of self-expandable metal stent placement for malignant distal biliary obstruction: a large multicenter study.

BACKGROUND AND AIMS: Endoscopic placement of self-expandable metal stents (SEMSs) for malignant distal biliary obstruction (MDBO) may be accompanied by several types of adverse events. The present study analyzed the adverse events occurring after SEMS placement for MDBO. METHODS: The present study retrospectively investigated the incidence and types of adverse events in patients who underwent SEMS placement for MDBO between April 2018 and March 2021 at 26 hospitals. Risk factors for acute pancreatitis, cholecystitis, and recurrent biliary obstruction (RBO) were evaluated by univariate and multivariate analyses. RESULTS: Of the 1425 patients implanted with SEMSs for MDBO, 228 (16.0%) and 393 (27.6%) experienced early adverse events and RBO, respectively. Pancreatic duct without tumor involvement (P = .023), intact papilla (P = .025), and SEMS placement across the papilla (P = .037) were independent risk factors for acute pancreatitis. Tumor involvement in the orifice of the cystic duct was an independent risk factor for cholecystitis (P < .001). Use of fully and partially covered SEMSs was an independent risk factor for food impaction and/or sludge. Use of fully covered SEMSs was an independent risk factor for stent migration. Use of uncovered SEMSs and laser-cut SEMSs was an independent risk factor for tumor ingrowth. CONCLUSIONS: Pancreatic duct without tumor involvement, intact papilla, and SEMS placement across the papilla were independent risk factors for acute pancreatitis, and tumor involvement in the orifice of the cystic duct was an independent risk factor for cholecystitis. The risk factors for food impaction and/or sludge, stent migration, and tumor ingrowth differed among types of SEMSs.

Thiopurines exert harmful effects on spermatogenesis in Nudt15R138C knock-in mice.

BACKGROUND: The association between thiopurine use and testicular reproductive functions remains unclear. In this study, we investigated whether thiopurines affect testicular functions based on the NUDT15 genotypes using Nudt15R138C knock-in mice. METHODS: The male Nudt15R138C knock-in mice (9-12 weeks) were treated with mercaptopurine (MP: 0.5 mg/kg/day) for 4 or 12 weeks. To examine reversibility, some mice were maintained for a further 12 weeks under MP-free condition. RESULTS: After MP treatment for 4 weeks, Nudt15R138C/R138C mice exhibited a significant reduction of testis weight compared to Nudt15+/+ mice and Nudt15+/R138C mice. The epithelial height and diameter of seminiferous tubules were significantly reduced in Nudt15R138C/R138C mice compared to Nudt15+/+ and Nudt15+/R138C mice. Apoptotic cells were significantly increased in Nudt15R138C/R138C mice, and most of apoptotic cells were spermatogonia. There were no significant changes in sperm counts and sperm morphology in MP-treated Nudt15R138C/R138C mice after 4-week MP treatment. On the other hand, after MP treatment for 12 weeks, the Nudt15+/R138C mice, but not Nudt15+/+ mice, exhibited a significant reduction in the testis weight and atrophic changes of seminiferous tubules, but these changes disappeared after 12-week rearing under MP-free condition. Despite a significant increase in abnormal sperm rate, there were no changes in the ability to conceive. No differences in serum levels of follicle-stimulating hormone or testosterone were observed between MP-treated Nudt15+/R138C and Nudt15+/+ mice after 12-week MP treatment. CONCLUSIONS: Thiopurines exert harmful effects on testicular reproductive function according to host NUDT15 genotypes.

A case of early gastric cancer with metastatic recurrence following curative endoscopic submucosal dissection.

A 70-year-old man was diagnosed with early gastric cancer with ulcerative findings. Endoscopic submucosal dissection as an absolute indication was performed, and en bloc resection was achieved. Pathological examination revealed a well-differentiated adenocarcinoma, 3 × 2 mm in size, intramucosal, with an ulcerative scar, no lymphovascular invasion, and a tumor-free margin. We diagnosed it as a curative resection and followed up with annual endoscopy. Sixteen months after endoscopic submucosal dissection, esophagogastroduodenoscopy revealed a singular ulcer scar; however, serum carcinoembryonic antigen level was elevated. Computed tomography scan showed wall thickening of the gastric antrum and an irregular mass on the dorsal side. Additionally, 18F-fluorodeoxyglucose positron emission tomography/coomputed tomography showed 18F-fluorodeoxyglucose uptake in the gastric antrum, irregular mass, and liver. Endoscopic ultrasonography revealed an internally heterogeneous mass in the gastric antrum region extending from the submucosal layer to the muscularis propria layer. Using an endoscopic ultrasonography-guided fine needle biopsy with a 22-gauge needle for the mass, we diagnosed local recurrence with the submucosal tumor-like appearance, lymph node metastasis, and liver metastases. Unfortunately, the patient died of gastric cancer 3 months after the diagnosis. Here, we report a rare case of local recurrence in the submucosal layer, lymph node metastasis, and liver metastases 16 months after curative endoscopic submucosal dissection.

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.

The diagnostic accuracy of endoscopic ultrasound-shear wave elastography in multiple pancreatic regions for chronic pancreatitis based on the Rosemont criteria.

PURPOSE: Although endoscopic ultrasound (EUS) has been widely used for diagnosing chronic pancreatitis (CP), the assessment of fibrosis using the Rosemont criteria (RC) is generally subjective. Shear wave elastography using EUS (EUS-SWE) has been advocated as an objective approach to evaluating pancreatic fibrosis; however, it is unknown which pancreatic region should be selected for measurement. This study aims to compare the diagnostic accuracy in diagnosing CP by measurement site. METHODS: Fifty patients with CP or suspected CP who underwent EUS-SWE were retrospectively analyzed. As per the RC, they were classified into two groups: CP and non-CP. Pancreatic stiffness was evaluated by measuring the velocities of the shear wave (Vs) in addition to determining the relevant cutoff value of Vs for diagnosing CP. The correlation between Vs and RC, and the RC factors affecting pancreatic stiffness were evaluated. RESULTS: In the CP group, the Vs were notably higher in all regions (P < 0.001). The Vs for diagnostic accuracy of CP were highest in the body [area under the curve (AUC): 0.87]. A significant correlation was seen between the number of RC and Vs in all regions, with the correlation coefficient being highest in the pancreatic body (rs = 0.55). Multivariate analysis revealed that lobularity with honeycombing was an independent factor for pancreatic stiffness (P = 0.02). CONCLUSION: The pancreatic body is a suitable region for assessing pancreatic stiffness using EUS-SWE. Additionally, quantifying Vs is a valuable objective indicator for diagnosing CP.

Single-Nucleotide Polymorphisms, c.415C > T (Arg139Cys) and c.416G > A (Arg139His), in the NUDT15 Gene Are Associated with Thiopurine-Induced Leukopenia.

While nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) gene polymorphism Arg139Cys (rs116855232) is known to be a risk factor for thiopurine-induced severe leukopenia, association with the NUDT15 gene polymorphism Arg139His (rs147390019) has not yet been clarified. In addition, the accuracy of TaqMan PCR to assess these two polymorphisms has not been investigated. In this study, we evaluated TaqMan PCR for detection of the NUDT15 single-nucleotide polymorphisms (SNPs) and examined the clinical impact of Arg139His on thiopurine-induced leukopenia. First, we demonstrated that a TaqMan PCR assay successfully detected the Arg139His polymorphism of NUDT15 in clinical samples. Next, the NUDT15 gene polymorphisms (Arg139Cys and Arg139His) were separately analyzed by TaqMan Real-Time PCR in 189 patients from August 2018 to July 2019. The incidences of leukopenia within 2 years were 16.2, 57.9, and 100% for arginine (Arg)/Arg, Arg/cysteine (Cys), and Arg/histidine (His), respectively. The leukopenia was significantly increased in Arg/Cys and Arg/His compared with Arg/Arg. This retrospective clinical study indicated that, in addition to Arg139Cys, Arg139His may be clinically associated with a high risk of leukopenia. Pharmacogenomics will help in selecting drugs and determining the individualized dosage of thiopurine drugs.

Bile duct penetrating duodenal wall sign: a novel computed tomography finding of common bile duct stone impaction into duodenal major papilla.

PURPOSE: Impacted common bile duct stones cause severe acute cholangitis. However, the early and accurate diagnosis, especially iso-attenuating stone impaction, is still challenging. Therefore, we proposed and validated the bile duct penetrating duodenal wall sign (BPDS), which shows the common bile duct penetrating the duodenal wall on coronal reformatted computed tomography (CT), as a novel sign of stone impaction. METHODS: Patients who underwent urgent endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis due to common bile duct stones were retrospectively enrolled. Stone impaction was defined by endoscopic findings as a reference standard. Two abdominal radiologists blinded to clinical information interpreted CT images to record the presence of the BPDS. The diagnostic accuracy of the BPDS to diagnose stone impaction was analyzed. Clinical data related to the severity of acute cholangitis were compared between patients with and without the BPDS. RESULTS: A total of 40 patients (mean age 70.6 years; 18 female) were enrolled. The BPDS was observed in 15 patients. Stone impaction occurred in 13/40 (32.5%) cases. Overall accuracy, sensitivity, and specificity were 34/40 (85.0%), 11/13 (84.6%), and 23/27 (85.2%), respectively; 14/16 (87.5%), 5/6 (83.3%), and 9/10 (90.0%) for iso-attenuating stones; and 20/24 (83.3%), 6/7 (85.7%), and 14/17 (82.4%) for high-attenuating stones. Interobserver agreement of the BPDS was substantial (κ = 0.68). In addition, the BPDS was significantly correlated with the number of factors in the systemic inflammatory response syndrome (P = 0.03) and total bilirubin (P = 0.04). CONCLUSION: The BPDS was a unique CT imaging finding to identify common bile duct stone impaction regardless of stone attenuation with high accuracy.

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.

Gastrojejunostomy versus endoscopic duodenal stent placement for gastric outlet obstruction in patients with unresectable pancreatic cancer: a propensity score-matched analysis.

BACKGROUND: Treatments for patients with gastric outlet obstruction (GOO) due to unresectable pancreatic cancers (URPC) include gastrojejunostomy (GJJ) and endoscopic duodenal stent placement (EDSP). This study compared the efficacy and safety of GJJ and EDSP in patients with GOO due to URPC. METHODS: This study retrospectively evaluated consecutive patients with GOO due to URPC who underwent GJJ or EDSP between April 2016 and March 2020. The efficacy and safety of GJJ and EDSP were compared with propensity score analysis. Subgroup analyses of overall survival (OS) were compared after propensity matching. RESULTS: Data were obtained from 54 patients who underwent GJJ and from 73 who underwent EDSP at five tertiary care hospitals. After propensity matching, OS was significantly longer in patients who underwent GJJ than EDSP (110 vs. 63 days, respectively; p = 0.019). Evaluation of long-term adverse events showed that the frequency of cholangitis and obstructive jaundice was significantly lower in the matched GJJ than in the matched EDSP group (p = 0.012). Subgroup analyses showed that OS in patients with good performance status (PS; p = 0.041), biliary obstruction (p = 0.007), and duodenal obstruction near the papilla (p = 0.027), and those receiving chemotherapy (p = 0.010), was significantly longer in the matched GJJ group than in matched EDSP group. CONCLUSION: GJJ provides longer OS than EDSP for patients with GOO caused by URPC, especially for patients with good PS, biliary obstruction, and duodenal obstruction near the papilla, and those receiving chemotherapy.

Steerable catheter based on wire-driven seamless artificial blood vessel tube for endoscopic retrograde transpapillary interventions.

PURPOSE: Current steerable catheters (SCs) for endoscopic retrograde cholangiopancreatography (ERCP) have performance limitations caused by an asymmetric multiple-slit tube design with a small maximum bend angle, lesser curvatures, and insufficient durability. We propose a wire-driven SC for balanced bidirectional bending using artificial blood vessel material to overcome these limitations. We assess the SC prototype's steerability using phantom and animal models. METHODS: The SC prototype employed a slit-less and multiple-lumen seamless tube with a polytetrafluoroethylene (PTFE) body with stretch-retractable porous expanded PTFE at the distal end, and loop-formed control wires. We evaluated the wire routing design using a static model. The bending performance was compared with conventional SCs. Feasibility studies were performed, including major duodenal papilla insertions and ductal branch selections in desktop phantoms and a mini-pig model. RESULTS: The proposed design reduced the wire contact force by 48% compared to the single wire configuration. The maximum bend angle was 162°, almost twofold larger than that for conventional SCs. The lateral tip position in the bent shape was maximally 56% smaller. The tip flexibility was comparable to conventional SCs, and the insertion resistance was similar to the passive catheters. Phantom studies showed that the SC prototype could perform the large and protuberant papilla insertions and fine ductal branch selections without breaking; the animal study was completed successfully. CONCLUSION: We propose a wire-driven SC design for ERCP using a multi-lumen seamless tube and two loop-formed control wires, different from the conventional SC design with a multiple-slit tube and single control wire. The SC prototype records balanced bidirectional bending with a maximum bending angle of ± 162° without breakage risk. The phantom and animal studies show that the prototype performance potentially facilitates papilla cannulations and intrahepatic ductal branch seeking.

Application and usefulness of a new eight-wire basket catheter for endoscopic extraction of small common bile duct stones: A retrospective multicenter study.

Objectives: Distally located small common bile duct stones are often difficult to treat or grasp endoscopically. Therefore, multiple devices, such as baskets or balloon catheters, are frequently used in such cases. However, it is desirable to use a single device for stone extraction from the perspective of cost-effectiveness. In this multicenter study, we evaluated the efficacy of a new eight-wire basket catheter for extracting small (≤10 mm) common bile duct stones. Methods: We retrospectively analyzed the records of 144 patients who underwent stone extraction using the eight-wire basket catheter for common bile duct stones ≤10 mm. The success rate of complete stone extraction and the risk factors for the difficulty in stone extraction with the eight-wire catheter alone were mainly evaluated. Results: The success rate of stone extraction with the eight-wire catheter alone was 86.1%. The final rate of complete stone extraction was 98.0%. The mean of the maximum diameter of the common bile duct and the largest stone dimension were 10.5 ± 3.5, and 5.1 ± 2.1 mm, respectively. Common bile duct diameter ≥12 mm and stone diameter ≥6 mm were identified as independent risk factors for the difficulty in stone extraction with the eight-wire catheter alone. Conclusions: The success rate of the new eight-wire basket for small common bile duct stone extraction was acceptable. The device is beneficial and could be used from the start for the extraction of small stones < 6 mm.

Altered gut microbiota in patients with small intestinal bacterial overgrowth.

BACKGROUND AND AIM: Small intestinal bacterial overgrowth (SIBO) is diagnosed by using quantitative culture of duodenal aspirates and/or a hydrogen breath test. However, few studies have analyzed bacterial microbiota in Japanese patients with SIBO. METHODS: Twenty-four patients with any abdominal symptoms and suspected SIBO were enrolled. Quantitative culture of duodenal aspirates and a glucose hydrogen breath test were performed on the same day. SIBO was diagnosed based on a bacterial count ≥ 103  CFU/mL or a rise in the hydrogen breath level of ≥ 20 ppm. The composition of the duodenal microbiota was analyzed by 16S rRNA gene sequencing. RESULTS: Small intestinal bacterial overgrowth was diagnosed in 17 of the 24 patients (71%). The positive rates for the hydrogen breath test and quantitative culture of duodenal aspirates were 50% and 62%, respectively. Patients with SIBO showed significantly reduced α-diversity compared with non-SIBO patients, and analysis of ß-diversity revealed significantly different distributions between SIBO and non-SIBO patients. In addition, the intestinal microbiome in SIBO patients was characterized by increased relative abundance of Streptococcus and decreased relative abundance of Bacteroides compared with non-SIBO patients. CONCLUSIONS: Duodenal dysbiosis was identified in patients with SIBO and may play a role in the pathophysiology of SIBO.

Effect of ice water injection toward the duodenal papilla for preventing post-ERCP pancreatitis: study protocol for a multicenter, single-blinded, randomized controlled trial (EUTOPIA study).

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is an essential procedure in the diagnosis and treatment of biliopancreatic diseases. The most common adverse event of ERCP is post-ERCP pancreatitis (PEP), which can sometimes be severe. Our previous study suggested that injecting ice water at the end of ERCP suppressed PEP, and we decided to investigate this effect in a multicenter randomized controlled trial. METHODS: This study is being conducted at eight hospitals in Japan starting in April 2022. Patients undergoing ERCP will be randomized to ice water group and control group. In the ice water group, 250 ml of ice water is injected toward the papilla at the end of ERCP. The next morning, a physical examination and blood tests are performed to evaluate for the development of pancreatitis. The goal is to have 440 cases in each group. DISCUSSION: The main cause of PEP is thought to be papilla edema. Cooling the papilla, as everyone naturally does at the time of a burn, is expected to prevent its inflammation and edema. Various methods to suppress PEP have been reported, but so far none of them are reliable. The method we have devised is very simple, easy, and safe. We hope that our study will change the world's ERCP common practice. TRIAL REGISTRATION: UMIN000047528. Registered 20 April 2022, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000053209.

[A case of obstructive jaundice due to the movement of pancreatic calculi].

A 44-year-old man with a history of chronic alcoholic pancreatitis and Crohn's disease presented with abdominal pain. Computed tomography revealed pancreatic calculi in the head of the pancreas and a dilated pancreatic duct. The patient was diagnosed with an acute exacerbation of chronic pancreatitis due to the impact of pancreatic calculi on the main pancreatic duct. During the clinical course, the movement of pancreatic calculi to the major papilla was confirmed, leading to obstructive jaundice. Endoscopic treatment with sphincterotomy of the pancreatic duct was successful. Herein, we report the case of an unusual clinical course involving obstructive jaundice caused by the movement of pancreatic calculi.