Background and AimRight colon polyps can especially be overlooked when they are located on the backs of haustral folds. Previous studies have reported that repeated forward‐view examinations in the right colon were effective in reducing adenoma miss rates. The aim of this study was to clarify the impact of retroflexion in the right colon after repeated forward‐view examinations.MethodsThis multicenter, prospective, observational study was conducted at three institutions in Kumamoto, Japan, between February 2014 and December 2015. Subjects who were over 40 years old and scheduled for colonoscopy were recruited. For the forward view, after cecal intubation, the colonoscope was withdrawn to the hepatic flexure. The colonoscope was sequentially reinserted to the cecum and then withdrawn to the hepatic flexure. For the retroflexion view (RV), the colonoscope was reinserted to the cecum, retroflexed, and then withdrawn to the hepatic flexure. All polyps were resected at the time of detection. The primary outcome of this study was the adenoma miss rate for the repeated forward‐view examinations.ResultsOf the 777 enrolled participants, retroflexion was successful in 730 (94.0%). The repeated forward‐view withdrawal technique detected 291 adenomas, while the third withdrawal in the RV detected 53. The adenoma miss rate for the repeated forward‐view withdrawal was 15.4%. No severe adverse events occurred during retroflexion.ConclusionBecause adenomas located on potential blind spots can be missed when only using forward‐view examinations, retroflexion in the right colon after repeated forward‐view examinations might improve colonoscopy detection rates.

Background: Adenocarcinoma with enteroblastic differentiation is a subtype of alpha-fetoprotein (AFP) producing adenocarcinoma. This type of tumor is associated with a poor prognosis and is prone to metastasize. Esophageal adenocarcinoma with enteroblastic differentiation is extremely rare.Case presentation: The patient was a 65-year-old woman who was referred to our hospital with dysphagia. Endoscopic examination revealed an elevated lesion 20mm in diameter at 17cm from the upper incisors. Endoscopic submucosa dissection (ESD) was performed and histopathological examination revealed tubular adenocarcinoma composed of cuboidal cells with clear cell cytoplasm. Immunohistochemical stain was diffusely positive for Sall-like protein 4 (SALL4) and weakly positive for AFP and glypican 3. From this result, we diagnosed esophageal adenocarcinoma with enteroblastic differentiation. The patient is still alive without recurrence of cancer 40 months after ESD.Conclusion: To our knowledge, this is the first report to undergo ESD for esophageal adenocarcinoma with enteroblastic differentiation arising from ectopic gastric mucosa in the esophagus.Abbreviations: AFP: alfa-fetoprotein; CA19-9: carbohydrate antigen 19-9; CEA: carcinoembryonic antigen; ESD: endoscopic submucosal dissection; EUS: endoscopic ultrasound; FDG-PET: [18F] fluorodeoxyglucose positron emission tomography; ME: magnifying endoscopy; NBI: narrow band imaging; SALL 4: Sall-like protein 4; SCC: squamous cell carcinoma antigen.

Background. Since gastrointestinal stromal tumor (GIST) is a mesenchymal submucosal tumor, the endosonographic, CT, and MRI features of gastric GISTs have been widely investigated. However, the GIST-bearing gastric mucosa status has not been reported. Objective. To characterize the GIST-bearing gastric mucosa status in terms of the degree of inflammation and atrophy, assessed endoscopically. Subjects and Methods. The subjects were 46 patients with submucosal tumors (histologically proven gastric GISTs) who had undergone upper gastrointestinal endoscopy in our hospital between April 2007 and September 2012. They were retrospectively evaluated regarding clinicopathological features, the endoscopically determined status of the entire gastric mucosa (presence or absence and degree of atrophy), presence or absence and severity of endoscopic gastritis/atrophy (A-B classification) at the GIST site, and presence or absence of H. pylori infection. Results. Twenty-three patients had no mucosal atrophy, but 17 and 6 had closed- and open-type atrophy, respectively. Twenty-six, 5, 12, 1, 1, and 1 patients had grades B0, B1, B2, B3, A0, and A1 gastritis/atrophy at the lesion site, respectively, with no grade A2 gastritis/atrophy. Conclusion. The results suggest that gastric GISTs tend to arise in the stomach wall with H. pylori-negative, nonatrophic mucosa or H. pylori-positive, mildly atrophic mucosa.

Objectives Endoscopic submucosal resection with band ligation (ESMR‐L) and endoscopic submucosal dissection (ESD) are both standard endoscopic resection methods for rectal neuroendocrine tumors (NETs) <10 mm in size. However, there is no definitive consensus on which is better. Here, we compared the efficacy of ESMR‐L and ESD for small rectal NETs. Methods This was a multicenter retrospective cohort study including 205 patients with rectal NETs who underwent ESMR‐L or ESD. Treatment outcomes were compared by univariate analysis, multivariate analysis, and inverse probability treatment weighting (IPTW) using propensity scores. Subgroup analysis evaluated the impact of the endoscopist's experience on the technical outcome. Results Eighty‐nine patients were treated by ESMR‐L and 116 by ESD. The R0 resection rate was not significantly different between the two (90% vs. 92%, p = 0.73). The procedure time of ESMR‐L was significantly shorter than for ESD (17 min vs. 52 min, p < 0.01) and the hospitalization period was also significantly shorter (3 days vs. 5 days, p < 0.01). These results were confirmed by multivariate analysis and also after IPTW adjustment. The procedure time of ESD was significantly prolonged by a less‐experienced endoscopist (49 min vs. 70 min, p = 0.02), but that of ESMR‐L was not affected (17 min vs. 17 min, p = 0.27). Conclusions For small rectal NETs, both ESMR‐L and ESD showed similar high complete resection rates. However, considering the shorter procedure time and shorter hospitalization period, ESMR‐L is the more efficient treatment method, especially for less‐experienced endoscopists.