Koji Matsuda

Research and development of artificial intelligence (AI) in the field of gastrointestinal endoscopy is progressing rapidly. In Japan alone, there are more than 10 AI‐assisted endoscopic medical devices that have received regulatory approval, and numerous randomized controlled trials have been published both domestically and internationally. However, the adoption of AI in clinical practice has not been smooth due to factors such as insufficient evaluation of the balance between clinical benefits and harms, unclear cost‐effectiveness, the lack of reliable guidelines, and the absence of established reimbursement systems for medical fees. Considering this situation, the Japan Gastroenterological Endoscopy Society (JGES) presents its perspective on the status of AI in endoscopic practice in the form of the following position statements. This comprises nine statements developed by the JGES AI Committee in collaboration with a diverse panel of members. These statements comprehensively address issues related to the quality of endoscopic examinations, cost‐effectiveness, clinical disadvantages, preparatory knowledge, medical safety, and legal responsibilities. They have been developed to be practical and useful in actual endoscopy settings.

Interventional endoscopic ultrasonography/endosongraphy (I‐EUS) procedures have rapidly evolved since their introduction three decades ago; however, the classification and terminology for these procedures remain unstandardized. To address this, the Subcommittee for Terminology of I‐EUS in the Japan Gastroenterological Endoscopy Society was established to define classifications and a glossary of I‐EUS terms. They categorized I‐EUS procedures into five types based on purpose and method: (i) EUS‐guided sampling; (ii) EUS‐guided through‐the‐needle examination; (iii) EUS‐guided drainage/anastomosis (EUS‐D/A); (iv) trans‐endosonographically/EUS‐guided created route (ESCR) procedures; and (v) EUS‐guided delivery. EUS‐guided sampling includes tissue acquisition and fluid sampling, classified by needle type into fine needle aspiration and fine needle biopsy. Through‐the‐needle examinations include imaging, measurements, and biopsies. EUS‐D/A includes organ drainage/anastomosis, fluid collection drainage, and digestive tract anastomosis. In the EUS‐D/A route, “anastomosis” is used for organ‐to‐organ procedures, whereas “tract” is for fluid drainage. ESCR is a newly proposed term for procedures via anastomosis or tract, such as endoscopic necrosectomy and EUS‐guided antegrade stenting. The term “trans‐luminal drainage/anastomosis stent” is used for stents that maintain the ESCR rather than treating strictures. EUS‐guided delivery involves the delivery of substances, such as fluids, drugs, medical devices, and energy. This proposed categorization and terminology aimed to clarify I‐EUS procedures and will require updates as new techniques and concepts emerge.

INTRODUCTION: This study investigated the detection rate of colorectal neuroendocrine neoplasms (NENs) using large-scale colonoscopy data. METHODS: This cross-sectional analysis used large-scale data from a Japanese multicenter observational study of colonoscopies performed from 2010 to 2020. RESULTS: Among 82,005 colonoscopy cases, colorectal NENs were identified in 71 (67 of which were neuroendocrine tumors), with a detection rate of 0.087% (95% confidence interval: 0.069–0.109). Most were small rectal lesions, with only 4 >10 mm in size and 3 located in the colon. DISCUSSION: The detection rate of colorectal NENs during colonoscopy is substantially higher than expected.

Objectives: Colonoscopy withdrawal times are associated with the adenoma detection rate (ADR). However, the relationship between ADR and cecal insertion time has been inadequately characterized. We aimed to evaluate endoscopist‐related factors involved in the ADR, including the average individual colonoscopy insertion and withdrawal times.Methods: This observational study used a colonoscopy database with pathology data from routine clinical practice in Japanese institutions. The odds ratios (OR) of endoscopist‐related factors related to ADRs were examined using a generalized linear mixed model.Results: Of the 186,293 colonoscopies performed during the study period, 47,705 colonoscopies by 189 endoscopists in four hospitals were analyzed for ADR. The overall ADR was 38.3% (95% confidence interval [CI] 37.8, 38.7). Compared to endoscopists with mean cecal insertion times of <5 min, the OR of ADR for those with mean cecal insertion times of 5–9, 10–14, and ≥15 min were 0.84 (95% CI 0.71, 0.99), 0.68 (95% CI 0.52, 0.90), and 0.45 (95% CI 0.25, 0.78), respectively. Compared to endoscopists with mean withdrawal times of <6 min, the OR of ADR for those with mean withdrawal times of 6–9, 10–14, and ≥15 min were 1.38 (95% CI 1.03, 1.85), 1.48 (95% CI 1.09, 2.02), and 1.68 (95% CI 1.04, 2.61), respectively. There were no significant differences in ADRs by endoscopist specialty, gender, or the total number of examinations performed.Conclusion: Individual mean colonoscopy insertion time was associated with ADR and might be considered as a colonoscopy quality indicator as well as withdrawal time.

Objectives: To examine whether reasonable detection rate of endoscopically diagnosed lesions as adenoma (“endoscopic” adenoma detection rate [ADR]) could be calculated with a database generated from colonoscopy reports and whether it could be used as a surrogate colonoscopy quality indicator of “pathological” ADR.Methods: A lesion‐by‐lesion database of colonoscopies performed between 2010 and 2020 at eight Japanese endoscopy centers and corresponding pathology database were integrated. Differences in numbers of detected polyps, “endoscopic” and “pathological” adenomas, and what these differences could be attributed to were examined. Polyp detection rate (PDR), “endoscopic” and “pathological” ADRs, and correlation coefficients between “pathological” ADR and PDR or “endoscopic” ADR by each endoscopist were calculated.Results: Overall, 129,065 colonoscopy reports were analyzed. Among a total of 146,854 polyps, more “endoscopic” adenomas (n = 117,359) were observed than “pathological” adenomas (n = 70,076), primarily because adenomas were not resected on site, rather than because of a misdiagnosis. In all patients analyzed, PDR, “endoscopic” and “pathological” ADRs were 56.4% (95% confidence interval [CI] 56.2–56.7), 48.0% (95% CI 47.7–48.3), and 32.7% (95% CI 32.5–33.0), respectively. “Endoscopic” and “pathological” ADRs from each endoscopist showed a high correlation in hospitals where adenomas were usually resected at the time of examination.Conclusions: By appropriately describing endoscopically diagnosed lesions as “adenomas” in endoscopy reports, “endoscopic” ADR might be used as a surrogate colonoscopy quality indicator of “pathological” ADR (UMIN000040690).

Objectives The Japan Endoscopy Database Project was initiated to develop the world’s largest endoscopy data repository. This study describes the first phase of the colonoscopy project in Japan. Methods Data were aggregated offline by integrating information from the endoscopy database software from January 2015 through March 2017. The study population included all patients who underwent colonoscopy at 8 centers. Results A total of 31,395 patients who underwent 38,497 colonoscopy procedures were registered. The majority of procedures were performed for screening (n=14,156), followed by fecal immunochemical test positivity (n=3,960), abdominal symptoms (n=3,864), post‐colorectal surgery surveillance (n=3,431), post‐endoscopic treatment surveillance (n=3,757), thorough pre‐treatment examination (n=2,822), and therapeutic purposes (n=6,507). In the screening group, advanced cancers, early cancers, and adenomas were diagnosed endoscopically in 2.1%, 1.3%, and 28.7% of cases, respectively, while in the fecal immunochemical test‐positive group, they were diagnosed in 2.5%, 1.9%, and 41.6% of cases, respectively. The incidence of complications was 0.177% and 0.152% in the screening and fecal immunochemical test‐positive groups, respectively. The therapeutic procedures included 1,446 cold forceps polypectomy procedures, 4,770 cold snare polypectomy procedures, 368 hot biopsies, 2998 hot snare polypectomy procedures, 9,775 endoscopic or piecemeal endoscopic mucosal resections, and 1,660 endoscopic submucosal dissections. A total of 173 procedure‐related complications (0.82%) occurred in 21,017 therapeutic procedures performed in 15,744 patients. Conclusions The first phase of the Japan Endoscopy Database Project established the proportions of the diagnostic and therapeutic colonoscopy procedures, and complication rates in real‐world settings.

Some situations may require endoscopy during the COVID-19 (Coronavirus Disease 2019) pandemic. Here, we describe the necessary precautions in the form of clinical questions and answers (Q&A) regarding the safe deployment of gastrointestinal endoscopy in such situations while protecting endoscopy staff and patients from infection. Non-urgent endoscopy should be postponed. The risk of infection in patients should be evaluated in advance by questionnaire and body temperature. The health of staff must be checked every day. Decisions to employ endoscopy should be based on the institutional conditions and aims of endoscopy. All endoscopic staff need to wear appropriate personal protective equipment (PPE). The endoscope and other devices should be cleaned and disinfected after procedures in accordance with the relevant guidelines. Optimal management of the endoscopy unit is required. Endoscopy for infected patients or those with suspected infection demands exceptional caution. When a patient who undergoes endoscopy is later found to have COVID-19, the members of staff involved are considered exposed to the virus and must not work for at least 14 days if their PPE is considered insufficient. When PPE resources are limited, some equipment may be used continuously throughout a shift as long as it is not contaminated. Details of the aforementioned protective measures are described.

All gastrointestinal endoscopic procedures have a high risk of aerosol contamination of the coronavirus disease 2019 (COVID‐19) to endoscopists, nurses, and healthcare assistants. Given the current pandemic situation of COVID‐19, the Japan Gastroenterological Endoscopy Society issued the recommendation for gastrointestinal (GI) endoscopy based on the status of COVID‐19 as of April 9, 2020, in Japan: (i) indications for GI endoscopy in the pandemic of COVID‐19; (ii) practical protective equipment for medical personnel depending on the risk for COVID‐19; (iii) preprocedural management, such as pharyngeal local anesthesia using lidocaine spray which has a potential to generate the aerosols; (iv) ideal settings of the endoscopy room including the numbers of the staff and the patients; (v) postprocedural management, such as undressing and follow‐up of the patients, as well as the involved staff, were documented to fit the practical scenarios in GI endoscopy, with the available data in Japan and the world. We believe that certain measures will prevent further spread of COVID‐19.

Background and AimFew studies have reported on a national, population-based endoscopic retrograde cholangiopancreatography (ERCP) database. Hence, in 2015, we established a multicenter ERCP database registry, the Japan Endoscopic Database (JED) Project in preparation for a nationwide endoscopic database. The objective the present study was to evaluate this registry before the establishment of a nationwide endoscopic database. MethodsFrom 1 January 2015 to 31 March 2017, we collected and analyzed the ERCP data of all patients who underwent ERCP in four participating centers in the JED Project based on the JED protocol. ResultsFour centers carried out 4104 ERCP on 2173 patients. Data entry of ERCP information (age, 100%; gender, 100%; American Society of Anesthesiologists Physical Status Classification System, 74.5%; scope, 92.7%; time to ERCP, 100%; antithrombotic drug information, 55.0%; primary selective common bile duct [CBD] cannulation methods, 73.0%; number of attempts at primary selective CBD cannulation, 67.6%; overall selective CBD cannulation methods, 68.9%; ERCP procedure time, 66.3%; fluoroscopy time, 65.1%; adverse events, 74.9%; serum amylase levels 1 day post-ERCP, 36.5%) was accurately extracted from the four centers. Success rate of CBD cannulation by level of ERCP difficulty was 98.5%, 99.0%, and 96.4% in grades 1, 2, and 3, respectively. Complication rate by overall selective CBD cannulation method was 5.6%, 7.6%, and 10.5% in the contrast-assisted technique, guidewire-assisted technique, and cross-over method, respectively. ConclusionData from this evaluation of the JED Project, a multicenter ERCP database registry, suggest the feasibility of establishing a nationwide ERCP database and its challenges.

Although esophagogastroduodenoscopy (EGD) is the most commonly used procedure in the gastrointestinal (GI) tract, the method of esophageal, gastric and duodenal mucosa photodocumentation varies considerably worldwide. One probable explanation is that for generations, EGD has primarily been taught by GI faculty and instructors based on their perceptions and experience, which has resulted in EGD being a non‐standardized procedure. Currently, the procedure is facing a challenging scenario as endoscopy societies are implementing procedure‐associated quality indicators aiming for best practice among practitioners and evidence‐based care for patients. Contrary to colonoscopy where cecum landmarks photodocumentation is considered proof of completeness, there are currently no reliable performance measures to gauge the completeness of an upper endoscopy nor guidance for complete photodocumentation. This World Endoscopy Organization (WEO) position statement aims to provide practical guidance to practitioners to carry out complete EGD photodocumentation. Hence, an international group of experts from the WEO Upper GI Cancer Committee formulated the following document using the body of evidence established through literature reviews, expert opinions, and other scientific sources. The group acknowledged that although the procedure should be feasible in any facility, what is needed to achieve a global shift on the concept of completeness is a common written statement of agreement on its potential impact and added value. This best practice statement offers endoscopists principles and practical guidance in order to carry out complete photodocumentation from the hypopharynx to the second duodenal portion.