Publications by authors named "Naohisa Yahagi"

Background: Surgical gastrojejunostomy is associated with relatively high morbidity and mortality rates. However, current experimental EUS-guided gastrojejunostomy information is limited.

Objective: To evaluate a novel EUS-guided gastrojejunostomy technique using a new enteric balloon and lumen-apposing metal stent.

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The efficacy of conventional radiation therapy for gastric cancer is controversial. In this study, we evaluated the in vitro and in vivo effects of continuous low-dose-rate irradiation by I-125 seeds on different histological types of gastric cancer cell lines. Three human gastric cancer cell lines (MKN74, MKN45, and NUGC4) were treated with or without continuous low-dose irradiation by I-125 seeds in vitro and in vivo.

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Esophageal achalasia is often associated with esophageal cancer. However, in many cases, esophageal cancer tends to be found in an advanced stage, with a poor prognosis. However, early-stage cancer was detected recently due to the advances in endoscopic instruments.

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Background: The topical antispasmodic agent l-menthol is useful for inhibiting gastric peristalsis during diagnostic upper gastrointestinal endoscopy. However, it remains unclear whether l-menthol is similarly effective during therapeutic endoscopy, thereby improving treatment outcomes in a clinical setting.

Methods: A total of 83 patients scheduled to undergo endoscopic treatment at 8 Japanese referral centers were randomly assigned to receive l-menthol or placebo.

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There is general agreement as to the value of postoperative surveillance and the effectiveness of colonoscopy in the early detection of metachronous colorectal lesions. In the present case, a 56-year-old woman with no family history of colon cancer underwent surveillance colonoscopy in which a metachronous flat adenoma was detected following an interval of 23 years after a colectomy and 20 years subsequent to treatment for uterine cancer. A second metachronous flat lesion histopathologically determined to be a submucosal (sm) deep invasive cancer with lymphovascular involvement was detected 12 months later.

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Endoscopic submucosal dissection (ESD) represents a significant advance in therapeutic endoscopy with the major advantage being the ability to achieve a higher en bloc resection rate for early stage lesions. Western endoscopists infrequently perform colorectal ESD (CR-ESD) because of the greater technical difficulty involved, longer procedure times, and increased risk of perforation. Specialized training and sufficient clinical experience are necessary to successfully perform ESDs, but a systematic education and training program has still not been established in Japan or elsewhere in the world.

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Background/aims: In endoscopic submucosal dissection (ESD), misdiagnosis of the tumor margin may lead to residual carcinoma, which we treat by secondary ESD (sESD) for local control.

Methods: 1,458 lesions of early gastric carcinoma were treated by ESD between July 2006 and November 2011. 33 lesions were resected with positive lateral margins.

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Endoscopic submucosal dissection (ESD) enables direct submucosal dissection so that even large early-stage gastrointestinal tumors can be resected en bloc. ESD has recently been applied to the colorectum since it was originally developed for use in the stomach. However, colorectal ESD is technically more difficult with an increased risk of perforation compared with gastric ESD.

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Various studies by Japanese endoscopists have demonstrated that colorectal endoscopic submucosal dissection (ESD) can overcome technical limitations of the endoscopic mucosal resection (EMR) technique such as piecemeal resection for flat lesions larger than 20 mm, resection of lesions involving the dentate line or the ileocecal valve and lesions with the non-lifting sign, and achieve higher en bloc resection rate. However, it is infrequently performed in Western countries in comparison with Japan, despite the advantages explained above. There are some differences between Japan and Western countries in environments and clinical settings for performing ESD in the colorectum.

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Aim: Peppermint oil solution was found to be effective for reducing gastric spasm during upper gastrointestinal endoscopy. The aim of the present study was to assess whether the gastric peristalsis-suppressing effect is dose-dependently induced by L-menthol, the major constituent of peppermint oil, and to determine the recommended dose of an L-menthol preparation.

Methods: In this phase II, multicenter, double-blind, dose-response study, 131 eligible patients were randomly assigned to receive 20 mL of 0.

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A series of studies about the potential usefulness of magnifying endoscopy with narrow-band imaging (NBI) for the diagnosis of gastric and colonic lesion is reviewed. Concerning the magnifying NBI appearances of gastric lesions, a light blue crest is a highly accurate sign of the presence of histological intestinal metaplasia. Also, the degree of irregularity of the mucosal and vascular pattern is correlated with the histological severity of Helicobacter pylori-associated chronic gastritis.

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Endoscopic submucosal dissection (ESD), an endoscopic procedure for the treatment of gastric epithelial neoplasia without lymph node metastases, spread rapidly, primarily in Japan, starting in the late 1990s. ESD enables en bloc resection of lesions that are difficult to resect using conventional endoscopic mucosal resection (EMR). However, in comparison to EMR, ESD requires a high level of endoscopic competence and a longer resection time.

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Background: Endoscopic submucosal dissection (ESD) demands a new level of endoscopic skill in Europe. A 2-day workshop was set up for trainees to carry out five ESD each in order to obtain the skill level required to perform ESD in the stomach or rectum. This study describes: (i) the workshop setup; (ii) the participant's performance; and (iii) the training effect on post-workshop clinical ESD performance.

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Background And Aims: The results of a phase III, placebo-controlled study demonstrated that endoscopic direct spraying of L: -menthol onto the gastric mucosa effectively suppressed gastric peristalsis in the study patients. The aim of the study reported here was to determine whether the anti-peristaltic effect of an L: -menthol preparation facilitates endoscopic examinations in a clinical setting.

Methods: This was a multicenter, open-label, single-arm trial in which the study cohort comprised patients in whom L: -menthol was likely to be used to facilitate endoscopic examination in clinical settings.

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We carried out a retrospective questionnaire survey of 792 submucosal colorectal carcinoma (CRC) cases from 15 institutions affiliated with the Colorectal Endoscopic Resection Standardization Implementation Working Group in Japanese Society for Cancer of the Colon and Rectum. In these cases, endoscopic resection (ER) and surveillance was carried out without additional surgical resection. Local recurrence or metastasis was observed in 18 cases.

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Background: GI peristalsis during GI endoscopy commonly requires intravenous or intramuscular injection of antispasmodic agents, which sometimes cause unexpected adverse reactions.

Objective: Our ultimate goal was to evaluate whether the antiperistaltic effect of L-menthol-based preparations facilitates endoscopic examinations in a clinical setting.

Design: Multicenter, randomized, double-blind, placebo-controlled study.

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Aims: The aims of the present study were to evaluate the feasibility of endoscopic submucosal dissection (ESD) as curative treatment for node-negative submucosal invasive early gastric cancer (EGC) and to consider further expansion of the curability criteria for submucosal invasive EGC.

Methods: A total of 977 EGC in 855 patients treated by ESD were enrolled. They were divided into intramucosal cancer (M); minimally submucosal invasive cancer (<500µm from the muscularis mucosa) (SM1); and deeper submucosal invasive cancer (>500µm from the muscularis mucosa) (SM2).

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Background And Aim: Intraoperative bleeding is an important determining factor for the technical difficulty and safety of endoscopic submucosal dissection (ESD) for gastric neoplasms, which was previously difficult to predict before ESD. In the present study, we investigated whether endoscopic ultrasound (EUS) could be used to preoperatively predict intraoperative bleeding.

Methods: The study included 106 patients who underwent EUS before ESD.

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Bleeding, perforation, and residual/local recurrence are the main complications associated with colonoscopic treatment of colorectal tumor. However, current status regarding the average incidence of these complications in Japan is not available. We conducted a questionnaire survey, prepared by the Colorectal Endoscopic Resection Standardization Implementation Working Group, Japanese Society for Cancer of the Colon and Rectum (JSCCR), to clarify the incidence of postoperative bleeding, perforation, and residual/local recurrence associated with colonoscopic treatment.

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Background And Study Aim: Residual or locally recurrent lesions may occur after endoscopic therapy for epithelial colorectal tumors. Additional endoscopic mucosal resection is difficult for large lesions. Endoscopic submucosal dissection may be useful for such lesions, but may be more technically difficult for residual/locally recurrent lesions than for primary lesions.

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The biggest topic of therapeutic endoscopy in recent years is a development of new therapeutic strategy for neoplasm of the gastrointestinal tract using endoscopic submucosal dissection (ESD) technique. Ever since the emergence of ESD, indication criteria for endoscopic resection of neoplasm were extended through expansion of both theoretical and technical conditions and use of ESD is rapidly becoming widespread. ESD could not only avert the surgical risk without the lack of equal curability of surgical operation, but also bring large benefit for the patients QOL.

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In order to understand the current use of endoscopic submucosal dissection (ESD) for the treatment of colorectal tumors in Japan, we administered a questionnaire survey to 1356 institutions all over the country. The subject of the survey was colorectal ESD performed from January 2000 to September 2008. Among the 1356 institutions, 391 (28.

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Few experts can deal appropriately with metastatic bone tumors in the present situation. We developed a questionnaire about zoledronic acid for doctors with several specialties, and analyzed the differences in treatment strategy among various doctors retrospectively. Breast surgeons, have used zoledronic acid appropriately based on accurate knowledge, but it has been used inappropriately by doctors of other specialties due to lack of knowledge.

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Aim: Endoscopic submucosal dissection was developed to address the shortcomings of conventional endoscopic mucosal resection. The present study evaluated the benefits of endoscopic submucosal dissection compared with conventional endoscopic mucosal resection for the treatment of neoplasms arising from the remnant stomach after gastrectomy or esophagectomy.

Methods: This study, which was designed as a historical control study, evaluated 22 gastric cancers in remnant cancers treated by conventional endoscopic mucosal resection and another 40 cancers treated by endoscopic submucosal dissection.

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Gastric submucosal tumor (SMT) is frequently found during screening endoscopy, but definitive diagnosis based on histological confirmation is relatively difficult. Even without accurate diagnosis before treatment, open or laparoscopic surgery is currently carried out to remove SMT. The purpose of this study was to demonstrate the feasibility of endoscopic submucosal dissection (ESD) in diagnostic treatment for submucosal tumor (SMT) of the stomach.

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