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Shimamura, Yuto

0000-0003-4107-9264

Mayo Clinic

Showa Medical University Koto Toyosu Hospital, Tokyo, Japan.

Citations 6

Computer‐aided detection for esophageal achalasia (with video)
Shiwaku, Hironari , Misawa, Masashi , Inoue, Haruhiro , Boškoski, Ivo , Shimamura, Yuto , Ikebuchi, Yuichiro , Ominami, Masaki , Htet, Hein , Messmann, H, Colosso, Bianca Maria Quarta , Repici, Alessandro , Stavropoulos, Stavros N. , Bechara, Robert , Sethi, Amrita, Beyna, Torsten , Santi, Esperanza Grace , Sharma, Prateek , Eleftheriadis, Nikolas, Minami, Hitomi, Haber, Gregory , Seewald, Stefan , Shiwaku, Akio, Shiwaku, Yoshiyuki, Mori, Kensaku, Costamagna, Guido , Shimamura, Yuto , Ikebuchi, Yuichiro , Iwaya, Yugo , Htet, Hein Myat Thu , Colosso, Bianca Maria Quarta , Bechara, Robert , Kahaleh, Michel , Beyna, Torsten , Jiang, Kai, Oda, Masahiro , Familiari, Pietro , Hayee, Bu , Ho, Khek Yu , So, Jimmy Bok Yan , Bhandari, Pradeep , Grimes, Kevin L. , Maselli, Roberta , Hassan, Cesare , Fukami, Norio , Kahaleh, Michel , Sethi, Amrita , Neuhaus, Horst Ekkehard , Chiu, Philip Wai Yan , Eleftheriadis, Nikolas, Draganov, Peter V. , Mori, Kensaku , Kudo, Shin‐ei , Hasegawa, Suguru

Digestive Endoscopy | June 12, 2025 | Volume: 37 | Issue: 8 | Pages: 851-861

10.1111/den.15028 Get It

ObjectivesAchalasia is an esophageal motility disorder that impairs quality of life and is often missed (20–50%) on endoscopy. A newly developed computer‐aided detection (CAD) software has shown high accuracy for achalasia diagnosis in preclinical settings. However, its benefit in a clinical setting remains unclear.MethodsBetween February and August 2023, 83 endoscopists from 27 centers assessed 50 randomized endoscopic videos (25 achalasia, 25 nonachalasia) without and with CAD. Endoscopists assessed videos without CAD, then with CAD after 2 months. The primary end‐point was improvement in sensitivity for nonexperienced endoscopists (no endoscopic experience of achalasia). Sensitivity, specificity, and accuracy with and without CAD were compared using the McNemar test.ResultsSensitivity for diagnosing achalasia increased significantly with CAD, rising from 74.2% (95% confidence interval [CI] 72.2–76.0%) to 91.2% (95% CI 89.9–92.4%) for all readers, showing a difference of 17.1% (95% CI 15.1–19.0%). Specifically, sensitivity improved from 66.9% (95% CI 63.6–70.0%) to 91.9% (95% CI 89.9–93.6%) among nonexperienced endoscopists, resulting in a difference of 25.0% (95% CI 21.7–28.4%), and from 79.5% (95% CI 77.1–81.8%) to 90.8% (95% CI 89.0–92.3%) among experienced endoscopists (endoscopic experience of at least one achalasia case), with a difference of 11.3% (95% CI 8.9–13.6%). Accuracy and specificity improved significantly with CAD assistance, regardless of reader's experience.ConclusionCAD improves achalasia detection by 17%, confirming preclinical results. The benefit was higher for nonexperienced endoscopists. CAD assistance may lead to prompt and effective treatment, minimizing the risk of false‐negative diagnosis in clinical practice.Trial registrationThis study was registered in the University Hospital Medical Information Network Clinical Trial Registry (https://www.umin.ac.jp/ctr/) number: UMIN000053047.
Position statement of the World Endoscopy Organization: Role of endoscopy in screening, diagnosis, and treatment of esophageal superficial squamous neoplasiaia
Hassan, Cesare , Goda, Kenichi, Iyer, Prasad G. , Awadhi, Sameer Al , Lehibi, Abed Al , Arantes, Vitor , Burgos, Herbert, Cerisoli, Cecilio L., Dawsey, Sanford, Fleischer, David, Fluxá, Fernando, Inoue, Haruhiro , John, Sneha , Khashab, Mouen A., Kothari, Shivangi , Lee, Yeong Yeh, Ngamruengphong, Saowanee , Sharara, Ala I. , Shimamura, Yuto , Varocha, Mahachai, Villa‐Gomez, Guido, Wang, Kenneth K. , Yip, Hon Chi , Sharma, Prateek , Lee, Yeong Yeh , Chiu, Philip Wai Yan , Emura, Fabian , G Iyer, Prasad, Kim, Gwang Ha , Shimamura, Yuto , Yip, Hon-Chi , Hassan, Cesare , Lee, Yeong Yeh , Antonelli, Giulio , Burgos, Herbert, Dawsey, Sanford, Draganov, Peter V. , González, Nicolás , Kashin, Sergey V. , Khashab, Mouen A. , Lee, Yeong Yeh, Remes Troche, José M , Varocha, Mahachai, Wang, Wen‐Lun

Digestive Endoscopy | December 26, 2024 | Volume: 37 | Issue: 5 | Pages: 470-489

10.1111/den.14967 Get It

Esophageal squamous cell carcinoma (ESCC) remains a significant global health challenge, being the sixth leading cause of cancer mortality with pronounced geographic variability. The incidence rates range from 125 per 100,000 in northern China to 1–1.5 per 100,000 in the United States, driven by environmental and lifestyle factors such as tobacco and alcohol use, dietary habits, and pollution. Major modifiable risk factors include tobacco and alcohol consumption, with a synergistic risk increase when combined. Nonmodifiable risk factors include previous diagnoses of head and neck squamous cell carcinoma (H&N SCC), achalasia, and prior radiotherapy. Prevention strategies must be tailored to specific regional burdens to efficiently allocate medical and financial resources. Gastrointestinal endoscopy is crucial in reducing ESCC burden through early detection and characterization of neoplastic changes, such as high‐grade dysplasia. Early diagnosis significantly improves survival rates, while endoscopic resection of noninvasive dysplasia can prevent ESCC onset, reducing treatment burden for advanced disease. Postresection surveillance can detect high‐risk metachronous lesions. Despite these benefits, endoscopic prevention faces challenges, including the lack of high‐level evidence supporting its efficacy, opportunity costs, the need for specialized training and techniques, and the requirement for advanced technology investments. This Position Statement from the World Endoscopy Organization (WEO) aims to address these challenges, supplying recommendations for the exploitation of endoscopic resources regarding the possible role of screening, quality, and training for the detection, characterization, resection, and surveillance of ESCC.
Peroral endoscopic myotomy as a treatment for Killian–Jamieson diverticulum (KJ-POEM)
Assefa, Redeat Libanos, Bejjani, Michael , Mehta, Amit , Shrigiriwar, Apurva , Shimamura, Yuto , Inoue, Haruhiro , Mandarino, Francesco Vito , Bowers, Steven P. , Arevalo, Martha, Andrisani, Gianluca , Sampath, Kartik, Khashab, Mouen A., Shimamura, Yuto , Mandarino, Francesco Vito , Lajin, Michael , Assefa, Redeat, Fayyaz, Farimah , Azzolini, Francesco , Li, Zhen , Robles‐Medranda, Carlos , Arevalo-Mora, Martha , Dhir, Vinay K. , Tanțău, Alina Ioana , Khashab, Mouen A.

Endoscopy International Open | September 18, 2024 | Volume: 12 | Issue: 10 | Pages: E1214-E1219

10.1055/a-2399-7464 Get It

Abstract Background and study aims Killian-Jamieson diverticulum (KJD) is a rare type of esophageal diverticulum that occurs in a specific area called the Killian-Jamieson space. Although surgery has been the conventional treatment for symptomatic KJD, minimally invasive endoscopic techniques, particularly Killian-Jamieson per-oral endoscopic myotomy (KJ-POEM), have emerged as an alternative. The aim of the study was to evaluate the effectiveness and safety of KJ-POEM in treating KJD. Patients and methods This was an international, multicenter, retrospective study that included patients who underwent KJ-POEM for symptomatic KJD from October 16, 2018 to April 12,2023. The primary outcome was clinical success, defined as complete or near-complete resolution of symptoms (i.e., post-procedure Kothari-Haber Score ≤ 2). Secondary outcomes were technical success (defined as successful completion of all procedural steps), rate and severity of adverse events (AEs), total procedure duration, and symptom recurrence during follow-up. Results A total of 13 patients (mean age 65.23 years, 6 female) with KJD and a mean pre-procedure Kothari-Haber Score of 6 (standard deviation [SD] 2.16) underwent KJ-POEM across 10 participating centers. Clinical success and technical success were achieved in all cases (100%) with a mean post-procedure Kothari-Haber Score of 0.91 (SD 0.99). There were no AEs and no cases of injury to the recurrent laryngeal nerve. Mean length of hospital stay was 1.09 days (SD 0.74). Mean follow-up time was 9.41 months (SD 10.07) post-procedure. There was no post-procedure symptom recurrence any patient. Conclusions KJ-POEM is a safe and effective alternative treatment for symptomatic KJD with excellent short/mid-term outcomes.
Risk scoring system for the preprocedural prediction of the clinical failure of peroral endoscopic myotomy: a multicenter case–control study
Tanaka, Shinwa , Sato, Hiroki , Shimamura, Yuto , Okada, Hiroki , Shiota, Junya , Sakae, Hiroyuki , Ominami, Masaki , Hata, Yoshitaka , Fukuda, Hisashi , Ogawa, Ryo , Tatsuta, Tetsuya , Yokomichi, Hiroshi , Inoue, Haruhiro , Sato, Hiroki , Shimamura, Yuto , Sakae, Hiroyuki , Hata, Yoshitaka , Abe, Hirofumi , Sato, Chiaki , Nakamura, Jun , Ikebuchi, Yuichiro

Endoscopy | June 15, 2022 | Volume: 55 | Issue: 03 | Pages: 217-224

10.1055/a-1876-7554 Get It

Abstract Background Peroral endoscopic myotomy (POEM) is effective for the management of achalasia and its variants; however, it can be ineffective in some patients. We aimed to develop and validate a risk scoring system to predict the clinical failure of POEM preoperatively. Methods Consecutive patients who underwent POEM in 14 high volume centers between 2010 and 2020 were enrolled in this study. Clinical failure was defined as an Eckardt score of ≥ 4 or retreatment. A risk scoring system to predict the short-term clinical failure of POEM was developed using multivariable logistic regression and internally validated using bootstrapping and decision curve analysis. Results Of the 2740 study patients, 112 (4.1 %) experienced clinical failure 6 months after POEM. Risk scores were assigned for three preoperative factors as follows: preoperative Eckardt score (1 point), manometric diagnosis (−4 points for type II achalasia), and a history of prior treatments (1 point for pneumatic dilation or 12 points for surgical/endoscopic myotomy). The discriminative capacity (concordance statistics 0.68, 95 %CI 0.62–0.72) and calibration (slope 1.15, 95 %CI 0.87–1.40) were shown. Decision curve analysis demonstrated its clinical usefulness. Patients were categorized into low (0–8 points; estimated risk of clinical failure < 5 %) and high risk (9–22 points; ≥ 5 %) groups. The proportions of clinical failure for the categories were stratified according to the mid-term outcomes (log-rank test, P < 0.001). Conclusions This risk scoring system can predict the clinical failure of POEM preoperatively and provide useful information when making treatment decisions.
Correction: Risk factors and long-term course of gastroesophageal reflux disease after peroral endoscopic myotomy: A large-scale multicenter cohort study in Japan
Shiwaku, Hironari , Sato, Hiroki , Shimamura, Yuto , Shiota, Junya , Ominami, Masaki , Sakae, Hiroyuki , Hata, Yoshitaka , Fukuda, Hisashi , Ogawa, Ryo , Tatsuta, Tetsuya , Yokomichi, Hiroshi , Inoue, Haruhiro , Sakae, Hiroyuki , Hata, Yoshitaka , Shimamura, Yuto , Abe, Hirofumi , Sato, Chiaki , Nakamura, Jun , Ikebuchi, Yuichiro , Hasegawa, Suguru

Endoscopy | March 1, 2022 | Volume: 54 | Issue: 09 | Pages: C13-C13

10.1055/a-1778-9730 Get It

Risk factors and long-term course of gastroesophageal reflux disease after peroral endoscopic myotomy: A large-scale multicenter cohort study in Japan
Shiwaku, Hironari , Sato, Hiroki , Shimamura, Yuto , Shiota, Junya , Ominami, Masaki , Sakae, Hiroyuki , Hata, Yoshitaka , Fukuda, Hisashi , Ogawa, Ryo , Tatsuta, Tetsuya , Yokomichi, Hiroshi , Inoue, Haruhiro , Sakae, Hiroyuki , Hata, Yoshitaka , Shimamura, Yuto , Abe, Hirofumi , Sato, Chiaki , Nakamura, Jun , Ikebuchi, Yuichiro , Hasegawa, Suguru

Endoscopy | February 16, 2022 | Volume: 54 | Issue: 09 | Pages: 839-847

10.1055/a-1753-9801 Get It

Abstract Background Gastroesophageal reflux disease (GERD) and reflux esophagitis remain problems after peroral endoscopic myotomy (POEM). This study aimed to elucidate the risk factors and long-term course of reflux esophagitis and symptomatic GERD after POEM. Methods This multicenter cohort study involved 14 high volume centers. Overall, 2905 patients with achalasia-related esophageal motility disorders treated with POEM were analyzed for reflux esophagitis, severe reflux esophagitis (Los Angeles classification C or D), and symptomatic GERD. Results Reflux esophagitis was diagnosed in 1886 patients (64.9 %). Age ≥ 65 years (risk ratio [RR] 0.85), male sex (RR 1.11), posterior myotomy (RR 1.12), esophageal myotomy > 10 cm (RR 1.12), and gastric myotomy > 2 cm (RR 1.17) were independently associated with reflux esophagitis. Severe reflux esophagitis was diagnosed in 219 patients (7.5 %). Age ≥ 65 years (RR 1.72), previous treatments (RR 2.21), Eckardt score ≥ 7 (RR 0.68), sigmoid-type achalasia (RR 1.40), and esophageal myotomy > 10 cm (RR 1.59) were factors associated with severe reflux esophagitis. Proton pump inhibitors (PPIs) were more effective for reflux esophagitis at 5-year follow-up (P = 0.03) than after 1 year (P = 0.08). Symptomatic GERD was present in 458 patients (15.9 %). Symptom duration ≥ 10 years (RR 1.28), achalasia diagnosis (RR 0.68), integrated relaxation pressure ≥ 26 (RR 0.60), and posterior myotomy (RR 0.80) were associated with symptomatic GERD. The incidence of symptomatic GERD was lower at 5-year follow-up compared with that after 1 year (P = 0.04), particularly in PPI users (P < 0.001). Conclusions The incidence of severe reflux esophagitis was low after POEM, but excessive myotomy for older patients with previous treatments should be avoided. Early phase symptomatic GERD is non-acid reflux dependent and the natural course is favorable, basically supporting conservative treatment.