Background/Aims: The aim of this study was to evaluate the safety and efficacy of partially covered self-expandable metallic stents (PCSEMS) in patients undergoing neoadjuvant chemo (radio) therapy (NAC) for pancreatic cancer (PC). Methods: This was a prospective multicenter study to evaluate the safety and efficacy of PCSEMS in patients receiving NAC for resectable and borderline resectable PC. The primary endpoint was the rate of recurrent biliary obstruction (RBO). Results: Twenty-six patients with PC (three with resectable PC and 23 with borderline resectable PC) who underwent NAC at seven Japanese centers were included in the analysis. Both the technical and functional success rates of PCSEMS placement were 100%. Early stent-related complications were observed in three patients (11.5%): mild pancreatitis (n=2) and mild liver abscess (n=1). The median time to surgery or palliation was 4.0 months. Surgical resection was eventually performed in 73.1% of patients, and stent removal during surgery was successful in all patients. RBO was observed in nine patients (34.6%): seven with stent occlusion, one with kinking and one with migration. The RBO rates in resected cases and nonresected cases were 36.8% and 28.6%, respectively. Conclusions Biliary drainage by PCSEMS was safe and feasible in patients undergoing NAC for resectable and borderline resectable PC.

In this study, we assessed a series of our cases in which endoscopic self-expandable metal stents (SEMSs) were used to treat malignant afferent loop obstruction (ALO) that arose after pancreaticoduodenectomy (PD). We retrospectively examined the records of 7 patients who underwent endoscopic SEMS placement for malignant ALO following PD. Clinical success was achieved in all cases. The median procedure time was 30 min (range, 15–50 min). There were no cases of stent occlusion, and no procedure-related adverse events were encountered. All patients died of their primary disease, and the median overall survival period was 155 days (range, 96–374 days). A re-intervention involving endoscopic ultrasound-guided hepaticogastrostomy combined with antegrade stenting was performed for obstructive jaundice and acute cholangitis in 1 case. In conclusion, endoscopic SEMS placement may be an effective and safe treatment for malignant ALO that arises after PD.

Background/Aims: Mucosal cutting biopsy (MCB) is useful for the histopathological diagnosis of gastric subepithelial tumors (SETs). However, there is little information on cases in which MCB did not establish a diagnosis. In the current study, we aimed to investigate the characteristics of cases in which MCB was unsuccessful. Methods: Cases in which MCB was used to histopathologically diagnose gastric SETs at Kobe University Hospital between August 2012 and October 2018 were retrospectively reviewed. Results: Forty-five cases in which MCB was used to diagnose 43 gastric SETs in 43 patients were analyzed. The median tumor size was 20 mm (range, 8–50 mm). Pathological examinations resulted in definitive and suspected diagnoses and no diagnosis in 29 (gastrointestinal stromal tumor: n=17, leiomyoma: n=7, aberrant pancreas: n=3, others: n=2), 6, and 10 cases, respectively. Failure to expose the tumor according to retrospective examinations of endoscopic images was significantly associated with no diagnosis. Other possible explanations included a less elevated tumor, biopsy of the surrounding field instead of the tumor due to the mobility, and poor endoscope maneuverability due to the tumor being close to the cardia. Conclusions Clear exposure of gastric SETs during MCB may improve the diagnostic rate of such examinations.

Background/Aims: Application of polyglycolic acid (PGA) sheets using fibrin glue in post-endoscopic submucosal dissection (ESD) ulcers to prevent bleeding has been reported to be difficult with the conventional delivery method because of gravity. This study assessed the usefulness of the envelope-based delivery system with and against gravity in living pigs. Methods: PGA sheets were applied on post-ESD ulcers with and against gravity six times each using the conventional and envelope methods, respectively. The PGA sheet delivery time and the endoscopic and histological findings of the treated ulcer floors were compared. Results: With gravity, the median PGA sheet application time was 1.00 (0.68–1.30) min/cm2 and 0.32 (0.18–0.52) min/cm2 with the conventional and envelope techniques (p=0.002), respectively, and against gravity, it was 1.20 (1.13–1.63) min/cm2 and 0.50 (0.39–0.58) min/cm2 (p=0.002), respectively. Against gravity, the endoscopic and histological findings revealed that the conventional group had insufficient fixation of the PGA sheets, but the envelope groups had sufficient fixation. The results with gravity were similar between the groups. Conclusions The envelope method makes it possible to deliver PGA sheets to the stomach quickly and cover ulcers appropriately both with and against gravity in living pigs.

Background/Aims: Endoscopic submucosal dissection (ESD) for diverticulum-associated colorectal lesions is generally contraindicated because of the high risk of perforation. Several studies on patients with such lesions treated with ESD have been reported recently. However, the feasibility and safety of ESD for lesions in proximity to a colonic diverticulum (D-ESD) have not been fully clarified. The aim of this study was to evaluate the feasibility and safety of D-ESD. Methods: D-ESD was defined as ESD for lesions within approximately 3 mm of a diverticulum. Twenty-six consecutive patients who underwent D-ESD were included. Two strategic approaches were used depending on whether submucosal dissection of the diverticulum-related part was required (strategy B) or not (strategy A). Treatment outcomes and adverse events associated with each strategy were analyzed. Results: The en bloc resection rate was 96.2%. The rates of R0 and curative resection in strategies A and B were 80.8%, 73.1%, 84.6%, and 70.6%, respectively. Two cases of intraoperative perforation and one case of delayed perforation occurred. The delayed perforation case required emergency surgery, but the other cases were managed conservatively. Conclusions D-ESD may be a feasible treatment option. However, it should be performed in a high-volume center by expert hands because it requires highly skilled endoscopic techniques.

Background/Aims: The anastomotic site after distal gastrectomy is the area most affected by duodenogastric reflux. Different reconstruction methods may affect the lesion characteristics and treatment outcomes of remnant gastric cancers at the anastomotic site. We retrospectively investigated the clinicopathologic and endoscopic submucosal dissection outcomes of remnant gastric cancers at the anastomotic site. Methods: We recruited 34 consecutive patients who underwent endoscopic submucosal dissection for remnant gastric cancer at the anastomotic site after distal gastrectomy. Clinicopathology and treatment outcomes were compared between the Billroth II and non-Billroth II groups. Results: The tumor size in the Billroth II group was significantly larger than that in the non-Billroth II group (22 vs. 19 mm; p=0.048). More severe gastritis was detected endoscopically in the Billroth II group (2 vs. 1.33; p=0.0075). Moreover, operation time was longer (238 vs. 121 min; p=0.004) and the frequency of bleeding episodes was higher (7.5 vs. 3.1; p=0.014) in the Billroth II group. Conclusions Compared to remnant gastric cancers in non-Billroth II patients, those in the Billroth II group had larger lesions with a background of severe remnant gastritis. Endoscopic submucosal dissection for remnant gastric cancers in Billroth II patients involved longer operative times and more frequent bleeding episodes than that in patients without Billroth II.

Autoimmune enteropathy (AIE) is a rare disease, characterized by intractable diarrhea, villous atrophy of the small intestine, and the presence of circulating anti-enterocyte autoantibodies. Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, and mutations in FOXP3, which is a master gene of regulatory T cells (Tregs), are major causes of AIE. Recent studies have demonstrated that mutations in other Treg-associated genes, such as CD25 and CTLA4, show an IPEX-like phenotype. We present the case of a 13-year-old girl with CTLA4 haploinsufficiency, suffering from recurrent immune thrombocytopenic purpura and intractable diarrhea. We detected an autoantibody to the AIE-related 75 kDa antigen (AIE-75), a hallmark of the IPEX syndrome, in her serum. She responded well to a medium dose of prednisolone and a controlled dose of 6-mercaptopurine (6-MP), even after the cessation of prednisolone administration. Serum levels of the soluble interleukin-2 receptor and immunoglobulin G (IgG) were useful in monitoring disease activity during 6-MP therapy. In conclusion, autoimmune-mediated mechanisms, similar to the IPEX syndrome, may be involved in the development of enteropathy in CTLA4 haploinsufficiency. Treatment with 6-MP and monitoring of disease activity using serum levels of soluble interleukin-2 receptor and IgG is suggested for such cases.

Background/Aims: Endoscopic self-expandable metal stent (SEMS) placement is currently the standard technique for treating unresectable malignant distal biliary obstructions (MDBO). Therefore, covered SEMS with longer stent patency and fewer migrations are required. This study aimed to assess the clinical performance of a novel, fully covered SEMS for unresectable MDBO. Methods: This was a multicenter single-arm prospective study. The primary outcome was a non-obstruction rate at 6 months. The secondary outcomes were overall survival (OS), recurrent biliary obstruction (RBO), time to RBO (TRBO), technical and clinical success, and adverse events. Results: A total of 73 patients were enrolled in this study. The non-obstruction rate at 6 months was 61%. The median OS and TRBO were 233 and 216 days, respectively. The technical and clinical success rates were 100% and 97%, respectively. Furthermore, the rate of occurrence of RBO and adverse events was 49% and 21%, respectively. The length of bile duct stenosis (<2.2 cm) was the only significant risk factor for stent migration. Conclusions The non-obstruction rate of a novel fully covered SEMS for MDBO is comparable to that reported earlier but shorter than expected. Short bile duct stenosis is a significant risk factor for stent migration.