The lumen-apposing metal stent (LAMS) is a fully covered, braided stent with bilateral anchor flanges. Fully expanded, the flanges are designed to hold tissue layers in apposition. This novel LAMS has been evaluated and found to have high technical and clinical success for endoscopic ultrasound (EUS)-guided pancreatic fluid collection. Since it has a large diameter, the upper gastrointestinal endoscope can be inserted into the stent lumen. The LAMS is also effective for necrosectomy against walled-off necrosis. In addition, there are reports of treatment methods in which the LAMS is used in EUS-guided choledochoduodenostomy and EUS-guided gallbladder drainage (EUS-GBD). There are also reports of removal of gallstones using the EUS-GBD route with the LAMS. As a new attempt to treat gastric outlet obstruction, EUS-guided gastrojejunostomy using the LAMS has been developed in recent years. The LAMS may provide more than several novel endoscopic therapeutic options as alternatives to surgery.

A 65-year-old man was referred to our department for further investigation of melena. The patient had been undergoing hemodialysis for nine years for end-stage renal disease (ESRD) due to diabetes mellitus, and had been receiving oral lanthanum carbonate for about seven years. Esophagogastroduodenoscopy (EGD) revealed oozing of blood in the antrum and a large number of fine white granules in the entire gastric mucosa. Hemostasis was achieved using argon laser via endoscopy. Biopsy specimens revealed brownish, granular mesh-like deposits in the lamina propria, leading to a diagnosis of lanthanum deposition in the gastric mucosa. The deposition tended to occur in regions of the gastric mucosa with intestinal metaplasia. There has only been one reported case of bleeding in the gastric mucosa with lanthanum deposition. Thus, we need to carefully observe and collect more data pertaining to such cases. Further investigations are required to assess the long-term effects of lanthanum deposition in the gastric mucosa.

A 40-year-old man was referred to our hospital for detailed examination of a gastric neoplasm. Esophagogastroduodenoscopy (EGD) revealed a flat elevated lesion of 10 mm in diameter in the lesser curvature of the antrum. Atrophy of gastric mucosa was not observed. Endoscopic submucosal dissection (ESD) of the lesion was performed. Histopathological examination revealed the lesion as a well-differentiated tubular adenocarcinoma that was confined to the mucosa with a clear resection margin. Immunohistochemical staining showed that the neoplasm was positive for CDX2 and CD10, and negative for MUC5AC and MUC6, which indicated that the lesion showed intestinal phenotype. Helicobacter pylori (HP) was negative in the histological examination, serum antibody test and urea breath test. The patient had no history of HP eradication therapy. This is a rare case of gastric cancer with intestinal phenotype in a patient who was not infected with HP.

A 46-year-old man was admitted to the hospital with acute abdominal pain. Abdominal palpation revealed epigastric tenderness without signs of peritoneal irritation. Abdominal contrast-enhanced computed tomography (CT) displayed a retroperitoneal hematoma with extravasation around the pancreatic head, while reconstructed CT images showed stenosis of the celiac axis. The patient was diagnosed with median arcuate ligament syndrome. Selective angiography of the superior mesenteric artery showed asymmetric dilation with slight extravasation from the posterior superior pancreaticoduodenal artery. The patient was successfully treated by performing transcatheter arterial embolization (TAE) using micro coils and was discharged on day 9 after admission. However, he was readmitted 7 days later with symptoms of nausea and vomiting. On upper gastrointestinal endoscopy, we discovered stenosis of the descending portion of the duodenum. Because his clinical symptoms were not severe, surgery was avoided and conservative treatment consisting of hyperalimentation and nasal gastric tube drainage was administered. His symptoms subsequently improved and he was discharged on day 45.

There are two potential causes of duodenal stenosis after TAE : compression by a hematoma or ischemia of the duodenal mucosa. Mucosal ischemia may be the result of either vascular obstruction caused by TAE or inflammation arising from a hematoma. In the present case, the hematoma showed a daily decrease in size and there was ample collateral circulation from the pancreaticoduodenal arcade. We therefore concluded that the primary cause of duodenal stenosis after the TAE was inflammation. This case suggests that duodenal stenosis after TAE may improve with conservative treatment if the surrounding inflammation resolves with reduction in size of the associated hematoma. Further investigation is needed to determine both the appropriate time course for conservative treatment and the indications for when surgery should be performed.

An 87-year-old woman developed massive gastrointestinal bleeding a week after starting 40mg of prednisolone per day. Upper gastrointestinal endoscopy revealed friable gastroduodenal mucosa with a white coat. Strongyloides stercoralis was identified in biopsy specimens taken from gastric and duodenal mucosal lesions and in the stool sample. After a two-week course of ivermectin 9 mg a day, her general condition improved. In the case of gastrointestinal bleeding in patients receiving immunosuppressive therapy, we should consider the diagnosis of intestinal parasitosis. The findings of mucosal biopsy can help to diagnose intestinal parasitosis especially when extensive superficial inflammation and bleeding are observed endoscopically.

[Purpose] The purpose of this study was to clarify the appropriate length of time required for trainees to attempt biliary cannulation.

[Methods] One hundred fifty-seven patients underwent endoscopic retrograde cholangiopancreatography (ERCP) for biliary cannulation by trainees between January 2015 and October 2016. We retrospectively evaluated the characteristics of native papilla in which it was difficult for trainees to perform biliary cannulation, by comparing the successful (n＝114) and failed (n＝43) biliary cannulation groups. We analyzed the risk factors for post-ERCP pancreatitis (PEP) and the appropriate length of time required for trainees to attempt biliary cannulation.

[Results] A significant characteristic of native papilla for difficult biliary cannulation was the length of oral protrusion ≥10 mm. Risk factors for PEP were the trainee’s cannulation time, length of oral protrusion ＜10 mm, and use of a metallic stent. The appropriate length of time required for trainees to attempt biliary cannulation was 11 min.

[Conclusion] We concluded that a prolonged attempt at cannulation was a significant risk factor for PEP. A length of time of 11 min was considered to be appropriate for trainees to attempt biliary cannulation.

Percutaneous transhepatic gallbladder drainage (PTGBD) is the first choice for drainage in patients with acute cholecystitis. Drainage by endoscopic gallbladder stenting (EGBS) is considered in cases in which the transhepatic procedure cannot be performed due to anticoagulant medication, existence of ascites, poor overall status, etc. However, the success rate of EGBS is still lower than that of PTGBD, and the degree of difficulty of EGBS varies according to the structure of the cystic duct. We may be able to improve the success rate of EGBS by using appropriate techniques and devices for the stent insertion procedure. If insertion is successful, the cholecystitis subsequently improves in almost all cases, and we can exchange the tube relatively easily. Thus, EGBS has the potential of becoming the treatment of choice in appropriate cases in the future.

Forceps biopsy and cytology during endoscopic retrograde cholangiopancreatography (ERCP) procedures are frequently performed in patients with pancreatobiliary diseases. However, the accuracy of these procedures has not been satisfactory. As for biliary diseases, a combination of bile duct biopsy and cytological examination including brush cytology could improve the accuracy of diagnosis. In addition, a recent study reported that a new endoscopic scraper demonstrated a large sample yield and high cancer detectability in malignant biliary strictures. As for pancreatic diseases, the accuracy of pancreatic duct biopsy for intraductal pancreatic tumor has not been satisfactory. Serial pancreatic-juice aspiration cytologic examination (SPACE) using pancreatic juice should be performed along with procedures such as pancreatic duct brushing and endoscopic nasopancreatic drainage (ENPD). A combination of pancreatic duct biopsy and cytology could improve the accuracy of detection and diagnosis of pancreatic diseases.

Background and Aim : The clinical impact of catheterbased radiofrequency ablation (RFA) under endoscopic retrograde cholangiopancreatography (ERCP) guidance has recently been reported ; however, severe adverse events have also been noted. If tumor is not present in the biliary tract, severe adverse events such as perforation or bleeding as a result of vessel injury around the biliary tract may occur. In addition, the effectiveness of RFA may not be sufficient based solely on radiographic guidance. The aim of the present study was to evaluate the actual feasibility of intraductal RFA by peroral cholangioscope (POCS) evaluation before/after RFA.

Methods : In this retrospective study carried out between July and September 2016, consecutive patients who underwent RFA for malignant biliary stricture and POCS evaluation before/after RFA were enrolled. Primary endpoint of this study was technical feasibility of RFA, which was evaluated by POCS. Secondary endpoints were rates and types of adverse event.

Results : A total of 12 consecutive patients were retrospectively enrolled in this study. Stent placement using uncovered metal stents had been previously done in six patients before RFA. Tumor was seen in the biliary tract in all patients. RFA was technically successful in all patients, and clinical success was confirmed in all patients by POCS imaging. Adverse events were seen in only one patient. Median stent patency was 154 days.

Conclusions : RFA for malignant biliary stricture may be safe. To confirm the feasibility and efficacy of RFA, additional cases, prospective studies, and a comparison study between with and without endobiliary RFA are needed.