Hirotsugu Maruyama

Trends and safety of small bowel endoscopy in Crohn’s disease in Japan: a large-scale claims database analysis

Background and study aims Self-expandable metal stents (SEMS) are widely used for malignant hilar biliary obstruction (MHBO), but whether they improve long-term drainage over plastic stents (PS) is uncertain. As chemotherapy prolongs survival, biliary drainage must be sustained across the remaining disease course. We compared failure of intended lifelong biliary drainage (LDF) between PS-based management and SEMS exposure using a causal inference framework. Patients and methods We retrospectively studied 608 consecutive patients who underwent initial endoscopic drainage for unresectable MHBO at 22 Japanese tertiary centers between January 2020 and March 2024. SEMS use was modeled as a time-varying, irreversible exposure. A marginal structural model with stabilized inverse probability of treatment and censoring weights estimated the adjusted odds ratio (OR) for LDF, defined as the point at which drainage could no longer be maintained by any endoscopic, EUS-guided, or percutaneous approach. Results Over a median follow-up of 184 days, 130 patients (21.4%) had LDF and 384 (63.2%) died. SEMS exposure was associated with higher odds of LDF (adjusted OR, 1.87; 95% CI, 1.28–2.73; P = 0.001), consistent across sensitivity analyses (OR range, 1.75–2.53). The association strengthened from 1.79 at 90 days to 2.93 at 450 days. Cumulative costs were higher in an exploratory analysis. Conclusions SEMS exposure was associated with higher odds of LDF and higher costs than PS-based management. These findings are hypothesis-generating, and prospective studies are needed to determine whether routine first-line SEMS use should be reconsidered when biliary drainage is intended to last across the remaining disease course.

Background and Aim: Metal (MS) or plastic stents (PS) are placed for preoperative biliary drainage (PBD) in patients with pancreatic ductal adenocarcinoma (PDAC) undergoing neoadjuvant chemotherapy (NAC) or chemoradiotherapy (NACRT). This multicentre retrospective study compared the safety and efficacy of PBD using MS and PS, including surgery‐related adverse events (AEs) and other clinical outcomes. Methods: This study enrolled patients with resectable or borderline resectable PDAC requiring NAC or NACRT who underwent PBD with MS or PS at 17 tertiary care hospitals in Japan between January 2016 and December 2021. Clinical outcomes were retrospectively analysed. Results: Of the 249 patients who underwent pancreatectomy, 121 underwent PBD with MS and 128 with PS. Because there were significant differences in baseline characteristics between these groups, propensity score matching was performed, resulting in 66 matched pairs. The RBO rate was significantly lower (15.2% vs. 56.1%, p < 0.001); the time to surgery ( p = 0.027) and postoperative hospital stay ( p = 0.036) were significantly shorter in the MS group. The incidence of postoperative AEs was significantly lower in the MS group (18.2% vs. 34.9%, p = 0.030) than in the PS group. Univariate and multivariate analyses identified the placement of an MS for PBD as an independent protective factor for postoperative AEs (odds rates: 0.35, p = 0.017). Conclusion: In patients with PDAC undergoing NAC or NACRT, MS placement for PBD was associated with lower rates of postoperative AEs and RBO than PS placement. MS is a more suitable option than PS for PBD.

Received: 27 April 2026 Accepted after revision: 12 May 2026 Article published online: 23 June 2026 © 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

Background/Aims: Pouchitis is a common complication in patients with ulcerative colitis (UC) following colectomy with ileal pouch-anal anastomosis (IPAA). Recent studies have identified a novel autoantibody against integrin αvβ6 in patients with UC, correlated with disease activity. This study aimed to assess the association between serum anti-integrin αvβ6 antibody levels and pouch inflammation in patients with postoperative UC. Methods: Serum anti-integrin αvβ6 antibodies were measured using enzyme-linked immunosorbent assay in patients after IPAA, patients with UC, and controls. Results: We examined sera from 71 subjects, including 28 patients who underwent IPAA, 23 controls, and 20 patients with mild and moderate-to-severe UC. Post-IPAA, patients with UC had higher median anti-integrin αvβ6 levels than that of controls (P<0.001) but lower than that of patients with active UC (P=0.001). Patients with pouchitis had higher antibody levels than those without (P=0.047). The receiver operating characteristics curve for anti-integrin αvβ6 showed an area under the curve of 0.724. The pouchitis activity index endoscopic sub-score was correlated with antibody levels (r= 0.48, P=0.011). Conclusions: Serum anti-integrin αvβ6 antibody levels remain elevated in patients with UC even after total colectomy, and were significantly higher in patients with pouchitis than in those without. This antibody could be a novel and useful biomarker for the diagnosis of pouchitis and assessment of disease activity.

Multidisciplinary treatment for malignant hilar biliary obstruction (MHBO) has improved, and biliary drainage has become increasingly important. Liver drainage of more than 80% is associated with prolonged survival [1]; however, the placement of three or more metal stents is technically challenging and therefore not commonly performed. Nevertheless, such extensive stenting may be required in cases of cholangitis or insufficient biliary drainage. Uncovered self-expandable metal stents (SEMSs) are generally used; however, they cannot be removed, and sequential stent insertion through the mesh becomes difficult. Herein, we report a case of MHBO with insufficient biliary drainage in which adequate drainage was successfully achieved by hybrid placement using three multi-hole self-expandable metal stents (MHSEMSs). A 72-year-old woman with hilar cholangiocarcinoma accompanied by peritoneal dissemination was undergoing chemotherapy. Plastic stents (PSs) had been placed in the right and left bile ducts ([Fig. 1]); however, liver enzyme levels remained elevated. To allow the stable continuation of chemotherapy, the PSs were exchanged for SEMSs. Cholangiography revealed bismuth type IV, with multiple strictures observed in the right anterior hepatic duct. To achieve more effective biliary drainage, the placement of three SEMSs was planned. First, three guidewires (GWs) were advanced into the target bile ducts, and the MHSEMSs were simultaneously deployed in the right and left bile ducts using a side-by-side placement. Subsequently, a GW was advanced into the right anterior hepatic duct through a hole in the right MHSEMS, and a third MHSEMS was deployed using a stent-in-stent placement ([Fig. 2]; [Video 1]). The procedure was completed without adverse events, and liver enzyme levels normalized. This method is expected to provide a longer patency period and a lower risk of tumor ingrowth [2]. Most importantly, because only a single passage through the stent mesh is required, this technique facilitates for trisegment drainage ([Fig. 3]) and is removable [3] [4]. Endoscopy_UCTN_Code_TTT_1AR_2AZ Article published online: 20 April 2026 © 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

Inside plastic stents (ISs) are widely used for malignant hilar biliary obstruction [1] [2]. In Japan, 7-Fr ISs are typically used, and when multiple stents are required, they are inserted sequentially. However, the placement of the second and subsequent ISs can be challenging due to severe tumor-related strictures and interference with the previously placed stent. Problems associated with placing an additional IS include proximal migration [3] [4] [5], the need for additional devices, and segmental cholangitis if the stent placement fails. Clinically, the occurrence of segmental cholangitis is a major issue as it requires repeated reinterventions and must therefore be avoided. Thus, endoscopists should aim for smooth stent deployment and timely completion of the procedure. To meet these clinical needs, a new 6-Fr IS (Olympus Optical Co., Tokyo, Japan) was developed ([Fig. 1]). Here, we report the successful simultaneous bilateral placement of this newly designed 6-Fr IS. A 78-year-old man with malignant hilar obstruction secondary to cholangiocarcinoma was referred for jaundice. Computed tomography and magnetic resonance cholangiopancreatography revealed a hilar stricture with marked bilateral intrahepatic duct dilatation ([Fig. 2]). During endoscopic retrograde cholangiopancreatography ([Video 1]), a 0.025-inch guidewire was inserted into the common bile duct, and fluoroscopy demonstrated a bismuth type IIIa hilar obstruction. Guidewires were then advanced into the left and anterior bile ducts. Two novel 6-Fr ISs were simultaneously introduced through the 4.2-mm working channel of a duodenoscope and successfully deployed in parallel without interference between the stents or with the guidewires ([Fig. 3]). The patient’s jaundice improved, and no adverse events occurred. This IS has minimal steps between the stent, inner sheath, and guidewire, reducing insertion resistance and facilitating smooth passage through biliary strictures. Simultaneous parallel placement using this novel stent may shorten procedure time, improve technical success, and serve as a promising option for future practice. Endoscopy_UCTN_Code_TTT_1AR_2AZ Endoscopy_UCTN_Code_CCL_1AZ_2AC Article published online: 09 March 2026 © 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

Complications of endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) have decreased with improved techniques and devices, with cholangitis and bleeding now being the most common [1]. Although fatal stent migration was previously a major concern, anti-migration stents have made it rare [2] [3]. Nevertheless, severe complications can still occur due to endoscopist inattention or misjudgment. In this case, a dedicated plastic stent migrated intraperitoneally because the placement relied solely on fluoroscopy alone. An additional EUS-HGS via B3 was performed, allowing the successful retrieval of the migrated stent through the new tract. A 66-year-old woman with prior gastrojejunostomy for duodenal obstruction due to cholecystitis was referred for cholangitis caused by intrahepatic stones. EUS-HGS was attempted by placing a dedicated plastic stent (PS). However, the stones prevented deep stent advancement, and it was inserted using fluoroscopic guidance alone. The stent was not seen endoscopically, leading us to conclude that it had been inadvertently deployed into the peritoneal cavity ([Fig. 1]). We then punctured B3 and placed a metal stent (MS) to create a wider drainage tract and reduce intraperitoneal leakage. Through the MS tract, we attempted to locate the PS fluoroscopically but could not identify it. Using a 22-gauge needle and a 0.018-inch guidewire, we accessed the PS in the hepatic parenchyma, but could not direct the guidewire toward the MS tract. Finally, we succeeded in advancing a GW into the lumen of the migrated PS via the MS route. Using a drill dilator, we were able to retrieve the stent into the stomach ([Video 1]). The postoperative course was uneventful ([Fig. 2]). This case serves as an important reminder that endoscopic and fluoroscopic imaging must be fully utilized. It also presents a method for retrieving a stent even if it migrates into the abdominal cavity, making it a very rare and valuable report. Endoscopy_UCTN_Code_TTT_1AS_2AH Article published online: 17 February 2026 © 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

Endoscopic biliary drainage for malignant hilar biliary obstruction should ideally allow for stent removal, regardless of the stent type [1]. When balloon assisted endoscopy (BAE) fails, interventional endoscopic ultrasound (EUS) becomes an alternative; however, in surgically altered anatomy, EUS-guided hepaticoduodenostomy is not indicated, and right-sided drainage via the left intrahepatic route is extremely challenging – especially when the entire procedure must be completed in one session, often preventing the placement of removable stents. In this case, because future chemotherapy was expected, stent removability was prioritized [2] [3]. After unsuccessful BAE, EUS-guided antegrade stenting was used to create a gateway, allowing the successful transpapillary stent-in-stent placement of multi-hole self-expandable metal stents (MHSEMSs). A 67-year-old woman who had undergone gastrojejunostomy for duodenal invasion caused by gallbladder cancer had two inside plastic stents (PSs) placed for obstructive jaundice. He was later admitted for the treatment of acute cholangitis. Because of the duodenal obstruction, reintervention was attempted using BAE through the bypass. Although the PSs were removed, biliary cannulation failed and drainage could not be achieved ([Fig. 1]). Since the major papilla was reachable, we employed a combined interventional EUS and endoscopic retrograde cholangiopancreatography (ERCP) approach. First, under EUS guidance, a MHSEMS was deployed antegradely to create a large transpapillary gateway that would allow easier access ([Fig. 2]). Then, a colonoscope (PCF-H290ZI; Olympus, Tokyo, Japan) was advanced to the major papilla, and using the MHSEMS as an access route, a guidewire was inserted into the right intrahepatic duct. Another MHSEMS was subsequently deployed ([Video 1], [Fig. 3]). The patient was discharged without any adverse events. This technique enables secure biliary access even in cases with poor endoscope maneuverability by creating a wide gateway and offers the advantages of removability and potentially prolonged stent patency. This approach represents a next-generation option that integrates the strengths of both EUS and ERCP. Endoscopy_UCTN_Code_TTT_1AS_2AH Article published online: 13 February 2026 © 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany