Interventional endoscopic ultrasound (EUS) is gaining acceptance as an effective method of managing a variety of conditions. EUS-guided fine-needle aspiration (EUS-FNA) has become a valuable tool for the diagnosis of lesions within the gastrointestinal tract and surrounding organs. It has proven to be an effective diagnostic method with high levels of accuracy and low complication rates. EUS-guided therapy can be categorized into 1) EUS-guided drainage, 2) EUS-guided celiac plexus block/neurolysis, and 3) others. More recently, EUS-guided gastrojejunostomy bypass for malignant gastric outlet obstruction has been established in the human setting. The possibility of interventional EUS has expanded the indications for EUS.

A long-term prognosis is expected in cases of PC < 1cm, and that dilatation of the pancreatic duct and the presence of a cystic lesion are important as indirect findings. When direct depiction of the tumor is difficult by ultrasonography (US) and dynamic multidetector computed tomography (MDCT), endoscopic ultrasonography (EUS) or magnetic resonance cholangiopancreatography (MRCP) should be performed.

The current clinical guidelines for pancreatic cancer (PC) in 2016 proposed that EUS-fine needle aspiration (FNA) should be performed when a mass lesion is detected by EUS and serial pancreatic juice aspiration cytologic examination (SPACE) should be performed when localized stenosis of the pancreatic duct, caliber change, and dilatation of the branch duct are found with endoscopic retrograde cholangiopancreatography (ERCP). Especially, SPACE is essential for diagnosis of PC in situ (PCIS). Recently, the Japan Study Group on the Early Detection of PC (JEDPAC) reported two hundred cases with Stage 0 and I. Image findings such as dilatation or irregular stenosis of the main pancreatic duct detected by CT, MRCP, or EUS were useful to detect early-stage PC. Preoperatively, SPACE followed by ERCP was more commonly applied than EUS-FNA. Recently, there have been some reports about tract seeding in the stomach after transgastric EUS-FNA. After performing SPACE, careful observation should be performed to avoid post-ERCP pancreatitis. The screening method including EUS for high-risk patients may be useful for the early diagnosis of PC. Some studies reported new diagnostic markers focusing on some genetic mutations or miRNAs in duodenal or pancreatic juice. From a recent prospective study, careful long-term follow-up including EUS should be performed in resected PC cases diagnosed at an early stage to check for recurrence in the remnant pancreas.

[Background and Objectives] Preventing colon cancer-related deaths via screening colonoscopy is less effective for the right colon than for the left colon. Therefore, the right colon requires more careful examination. We investigated the efficacy and safety of right colon retroflexion during colonoscopic examination.

[Methods] Randomized controlled trials were assessed to compare two forward-view examinations against one forward-view examination with an additional retroflexion view during colonoscopic examination of the right colon. We included randomized controlled studies in which the subjects were over 18 years old and underwent colonoscopy. MEDLINE (PubMed), the Cochrane Central Register of Controlled Trials (CENTRAL), Embase, the International Clinical Trials Registry Platform (ICTRP), and Igaku Chuo Zasshi (a Japanese medical literature database) were used to search for studies from May 2017 to June 2017. We performed a meta-analysis on data extracted using a random effects model. The quality of evidence was evaluated according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement．The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO registration number: CRD 42017062538).

[Results] Only two randomized controlled trials were deemed eligible, from which 948 subjects were selected. No studies reported subsequent colon cancer-related deaths or colon cancer incidence. The risk ratio of detection of additional adenomas, sized ≥10 mm, in the right colon, detected in the second retroflexion examination in the right colon, was 0.89 (95% confidence interval [CI] 0.26-3.05, P=0.85). There was no increase in detection of additional adenomas ≥10 mm in size by adding the retroflexion view compared with two forward-view examinations. The risk ratio of detection of additional adenomas of any size in the right colon was 0.76 (95% CI 0.55-1.05, P=0.10). The detection rate of additional adenomas of any size in the retroflexion group was decreased compared with that in the two forward-view examinations group, although the difference was not significant. There were no cases of perforation or bleeding. The quality of evidence for each outcome was low.

[Limitation] Synthesizing the available research was one of the limitations in this study, because of the varying definitions of the extent of the right colon that was investigated (to the level of the hepatic flexure or the splenic flexure). A second limitation was that only two eligible articles were found.

[Conclusion] We found that there was limited evidence for the efficacy of retroflexion views of the right colon. There was no evidence of superiority of detection by adding the right-colon retroflexion view to one forward-view examination, compared with two forward-view examinations.

A woman with recessive dystrophic epidermolysis bullosa was referred to our department from the department of dermatology because of dysphagia. We found esophageal stenosis and a brownish area using narrow band imaging in the middle esophagus by endoscopic examination. The brownish area was diagnosed as a low-grade intraepithelial neoplasia by biopsy. Because of lockjaw due to the underlying disease, endoscopic submucosal dissection would have been difficult to perform. We chose argon-plasma coagulation and the neoplasia was successfully treated.

A 78-year-old man underwent percutaneous endoscopic gastrostomy (PEG) seven years previously at our hospital. He was referred to our hospital at the present time because of tube obstruction and leakage of nutrients from the PEG tube. We performed esophagogastroduodenoscopy (EGD), endoscopic ultrasonography (EUS) and computed tomographic scanning, and diagnosed the patient with buried bumper syndrome in which the bumper of the PEG tube was buried in the gastric submucosa. We could not remove the bumper percutaneously.

On EGD, we cut the mucous membranes and submucosa on the buried bumper with grasping-type scissors forceps to expose the bumper, removed the bumper orally, and inserted a new PEG tube.

A 79-year-old man was admitted to our hospital because of epigastralgia and vomiting. Computed tomographic findings suggested gastric outlet obstruction (GOO) due to advanced antral gastric cancer and acute pneumonia owing to pulmonary aspiration. Since drainage from the stomach by insertion of a nasogastric tube was ineffective, we performed endoscopic stent placement for malignant pyloric stenosis. The patient recovered from the pneumonia after stent placement and underwent gastrectomy without postoperative complications. Preoperative endoscopic stent placement for malignant GOO could contribute to a better clinical outcome postoperatively.

Muscle-retracting sign (MR sign) is sometimes seen in large protruded-type lesions of the colon during endoscopic submucosal dissection (ESD). Exfoliation must be discontinued when MR sign is observed during ESD. However, it is difficult to predict whether MR sign will be present before the ESD procedure. We experienced three cases in which the ESD procedure had to be discontinued due to MR sign at our hospital. In an attempt to predict the presence of MR sign before ESD, miniature probe endoscopic ultrasonography (mEUS, 20MHz) has been performed at our hospital. Endoscopic ultrasonography (EUS)-MR sign was defined as positive when the muscle layer extends continuously from the base of the lesion to the inside of the lesion on mEUS. As a result, among 8 patients who underwent mEUS, 3 were positive for EUS-MR sign and these three patients were positive for MR sign during ESD as well. Among the five EUS-MR sign-negative patients, all of them showed negative MR sign during ESD. Findings from EUS-MR signs were consistent with the presence or absence of MR sign in all cases. These results may indicate that EUS is one of the procedures that can preoperatively predict the presence of MR sign which has been considered difficult.

Since endoscopic screening in the laryngopharynx area has been practiced more routinely, endoscopically treatable lesions have become discovered more often. We expected that the importance of endoscopic diagnosis and therapy would increase further in this field. We discuss contrivance of endoscopic diagnosis and therapy for laryngopharynx cancer.

Background and Aim: Cholecystitis is a major complication after self-expandable metallic stent (SEMS) placement for malignant biliary obstruction. Ischemia is one of the risk factors for cholecystitis, but little is known about the influence of tumor invasion to the feeding artery of the gallbladder on the onset of cholecystitis after SEMS placement. The aim of the present study was to identify risk factors for cholecystitis after SEMS placement.

Methods: Incidence and nine predictive factors of cholecystitis were retrospectively evaluated in 107 patients who underwent SEMS placement for unresectable distal malignant biliary obstruction at Kyoto University Hospital and Otsu Red Cross Hospital between January 2012 and June 2016.

Results: Cholecystitis occurred in 13 of 107 patients (12.1%) after SEMS placement during the median follow-up period of 262 days. Univariate analyses showed that tumor invasion to the feeding artery of the gallbladder and tumor involvement to the orifice of the cystic duct were significant predictors of cholecystitis (P＝0.001 and P＜0.001). Multivariate analysis confirmed that these two factors were significant and independent risks for cholecystitis with odds ratios of 22.13 (95% CI, 3.57-137.18; P＝0.001) and 25.26 (95% CI, 4.12-154.98; P＜0.001), respectively.

Conclusions: This study showed for the first time that tumor invasion to the feeding artery of the gallbladder as well as tumor involvement to the orifice of the cystic duct are independent risk factors for cholecystitis after SEMS placement.