Comparison of the efficacy and tolerability of elobixibat plus sodium picosulfate with magnesium citrate and split-dose 2-L polyethylene glycol with ascorbic acid for bowel preparation before outpatient colonoscopy: a study protocol for the multicentre, randomised, controlled E-PLUS trial.

BACKGROUND: Sodium picosulfate (SP)/magnesium citrate (MC) and polyethylene glycol (PEG) plus ascorbic acid are recommended by Western guidelines as laxative solutions for bowel preparation. Clinically, SP/MC has a slower post-dose defaecation response than PEG and is perceived as less cleansing; therefore, it is not currently used for major bowel cancer screening preparation. The standard formulation for bowel preparation is PEG; however, a large dose is required, and it has a distinctive flavour that is considered unpleasant. SP/MC requires a small dose and ensures fluid intake because it is administered in another beverage. Therefore, clinical trials have shown that SP/MC is superior to PEG in terms of acceptability. We aim to compare the novel bowel cleansing method (test group) comprising SP/MC with elobixibat hydrate and the standard bowel cleansing method comprising PEG plus ascorbic acid (standard group) for patients preparing for outpatient colonoscopy. METHODS: This phase III, multicentre, single-blind, noninferiority, randomised, controlled, trial has not yet been completed. Patients aged 40-69 years will be included as participants. Patients with a history of abdominal or pelvic surgery, constipation, inflammatory bowel disease, or severe organ dysfunction will be excluded. The target number of research participants is 540 (standard group, 270 cases; test group, 270 cases). The primary endpoint is the degree of bowel cleansing (Boston Bowel Preparation Scale [BBPS] score ≥ 6). The secondary endpoints are patient acceptability, adverse events, polyp/adenoma detection rate, number of polyps/adenomas detected, degree of bowel cleansing according to the BBPS (BBPS score ≥ 8), degree of bowel cleansing according to the Aronchik scale, and bowel cleansing time. DISCUSSION: This trial aims to develop a "patient-first" colon cleansing regimen without the risk of inadequate bowel preparation by using both elobixibat hydrate and SP/MC. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCT; no. s041210067; 9 September 2021; https://jrct.niph.go.jp/ ), protocol version 1.5 (May 1, 2023).

An Analysis of Delayed Bleeding in Cases of Colorectal Endoscopic Submucosal Dissection Due to Types of Direct Oral Anticoagulants in Japan.

BACKGROUND & AIMS: Reported rates of delayed bleeding (DB) after endoscopic resection using direct oral anticoagulants (DOACs) are high and heterogeneous. This large-scale multicenter study analyzed cases of DB after colorectal endoscopic submucosal dissection related to various types of DOACs in Japan (the ABCD-J study) with those associated with warfarin. METHODS: We retrospectively reviewed 1019 lesions in patients treated with DOACs and 459 lesions in patients treated with warfarin among 34,455 endoscopic submucosal dissection cases from 47 Japanese institutions between 2012 and 2021. The DB rate (DBR) with each DOAC was compared with that with warfarin. Risk factors for DB in patients treated with DOACs or warfarin were also investigated. RESULTS: The mean tumor sizes in the DOAC and warfarin groups were 29.6 ± 14.0 and 30.3 ± 16.4 mm, respectively. In the DOAC group, the DBR with dabigatran (18.26%) was significantly higher than that with apixaban (10.08%, P = .029), edoxaban (7.73%, P = .001), and rivaroxaban (7.21%, P < .001). Only rivaroxaban showed a significantly lower DBR than warfarin (11.76%, P = .033). In the multivariate analysis, heparin bridging therapy (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.27-3.73, P = .005), rectal location (2.01, 1.28-3.16, P = .002), and procedure time ≥55 minutes (2.43, 1.49-3.95, P < .001) were significant risk factors for DB in the DOAC group. The DB risk in the DOAC group (OR, (95% CI)) was 2.13 (1.30-3.50) and 4.53 (2.52-8.15) for 1 and 2 significant risk factors, respectively. CONCLUSIONS: Dabigatran was associated with a higher DBR than other DOACs, and only rivaroxaban was associated with a significantly lower DBR than warfarin.

Endoscopic Removal of Premalignant Lesions Reduces Long-Term Colorectal Cancer Risk: Results From the Japan Polyp Study.

BACKGROUND & AIMS: To date, no regional evidence of long-term colorectal cancer (CRC) risk reduction after endoscopic premalignant lesion removal has been established. We aimed to analyze this over a long-term follow-up evaluation. METHODS: This was a prospective cohort study of participants from the Japan Polyp Study conducted at 11 Japanese institutions. Participants underwent scheduled follow-up colonoscopies after a 2-round baseline colonoscopy process. The primary outcome was CRC incidence after randomization. The observed/expected ratio of CRC was calculated using data from the population-based Osaka Cancer Registry. Secondary outcomes were the incidence and characteristics of advanced neoplasia (AN). RESULTS: A total of 1895 participants were analyzed. The mean number of follow-up colonoscopies and the median follow-up period were 2.8 years (range, 1-15 y) and 6.1 years (range, 0.8-11.9 y; 11,559.5 person-years), respectively. Overall, 4 patients (all males) developed CRCs during the study period. The observed/expected ratios for CRC in all participants, males, and females, were as follows: 0.14 (86% reduction), 0.18, and 0, respectively, and 77 ANs were detected in 71 patients (6.1 per 1000 person-years). Of the 77 ANs detected, 31 lesions (40.3%) were laterally spreading tumors, nongranular type. Nonpolypoid colorectal neoplasms (NP-CRNs), including flat (<10 mm), depressed, and laterally spreading, accounted for 59.7% of all detected ANs. Furthermore, 2 of the 4 CRCs corresponded to T1 NP-CRNs. CONCLUSIONS: Endoscopic removal of premalignant lesions, including NP-CRNs, effectively reduced CRC risk. More than half of metachronous ANs removed by surveillance colonoscopy were NP-CRNs. The Japan Polyp Study: University Hospital Medical Information Network Clinical Trial Registry: University Hospital Medical Information Network Clinical Trial Registry, C000000058; cohort study: UMIN000040731.

Short-term outcomes of endoscopic resection for colorectal neuroendocrine tumors: Japanese multicenter prospective C-NET STUDY.

OBJECTIVES: The incidence of colorectal neuroendocrine tumors (NETs) has increased with colorectal cancer screening programs and increased colonoscopies. The management of colorectal NETs has recently shifted from radical surgery to endoscopic resection. We aimed to evaluate the short-term outcomes of various methods of endoscopic resection for colorectal NETs. METHODS: Among those registered in the C-NET STUDY, patients with colorectal NETs who underwent endoscopic treatment as the initial therapy were included. Short-term outcomes, such as the en bloc resection rate and R0 resection (en bloc resection with tumor-free margin) rate, were analyzed based on treatment modalities. RESULTS: A total of 472 patients with 477 colorectal NETs received endoscopic treatment. Of these, 418 patients with 421 lesions who met the eligibility criteria were included in the analysis. The median age of the patients was 55 years, and 56.9% of them were men. The lower rectum was the most commonly affected site (88.6%), and lesions <10 mm accounted for 87% of the cases. Endoscopic submucosal resection with a ligation device (ESMR-L, 56.5%) was the most common method, followed by endoscopic submucosal dissection (ESD, 31.4%) and endoscopic mucosal resection using a cap (EMR-C, 8.5%). R0 resection rates <10 mm were 95.5%, 94.8%, and 94.3% for ESMR-L, ESD, and EMR-C, respectively. All 16 (3.8%) patients who developed treatment-related complications could be treated conservatively. Overall, 23 (5.5%) patients had incomplete resection without independent clinicopathological risk factors. CONCLUSION: ESMR-L, ESD, and EMR-C were equally effective and safe for colorectal NETs with a diameter <10 mm.

First report from the International Evaluation of Endoscopic classification Japan NBI Expert Team: International multicenter web trial.

OBJECTIVES: Narrow-band imaging (NBI) contributes to real-time optical diagnosis and classification of colorectal lesions. The Japan NBI Expert Team (JNET) was introduced in 2011. The aim of this study was to explore the diagnostic accuracy of JNET when applied by European and Japanese endoscopists not familiar with this classification. METHODS: This study was conducted by 36 European Society of Gastrointestinal Endoscopy (ESGE) and 49 Japan Gastroenterological Endoscopy Society (JGES) non-JNET endoscopists using still images of 150 lesions. For each lesion, nonmagnified white-light, nonmagnified NBI, and magnified NBI images were presented. In the magnified NBI, the evaluation area was designated by region of interest (ROI). The endoscopists scored histological prediction for each lesion. RESULTS: In ESGE members, the sensitivity, specificity, and accuracy were respectively 73.3%, 94.7%, and 93.0% for JNET Type 1; 53.0%, 64.9%, and 62.1% for Type 2A; 43.9%, 67.7%, and 55.1% for Type 2B; and 38.1%, 93.7%, and 85.1% for Type 3. When Type 2B and 3 were considered as one category of cancer, the sensitivity, specificity, and accuracy for differentiating high-grade dysplasia and cancer from the others were 59.9%, 72.5%, and 63.8%, respectively. These trends were the same for JGES endoscopists. CONCLUSION: The diagnostic accuracy of the JNET classification was similar between ESGE and JGES and considered to be sufficient for JNET Type 1. On the other hand, the accuracy for Types 2 and 3 is not sufficient; however, JNET 2B lesions should be resected en bloc due to the risk of cancers and JNET 3 can be treated by surgery due to its high specificity.

Assessment of predictive factors associated with the technical difficulty of endoscopic submucosal dissection for superficial esophageal squamous cell carcinoma: Japanese multicenter retrospective study.

OBJECTIVES: Endoscopic submucosal dissection (ESD) for superficial esophageal squamous cell carcinoma (ESCC) is performed for the treatment of lesions with varied backgrounds and factors. However, the predictive factors associated with the technical difficulty of ESD remain unknown in patients with varied lesions. Therefore, this study aimed to identify the predictive factors associated with the technical difficulty of ESD for ESCC using a retrospective cohort. METHODS: This multicenter, retrospective study was conducted in 10 hospitals in Japan. Consecutive patients who underwent esophageal ESD between January 2013 and December 2019 were enrolled. Lesions of subepithelial tumors, adenocarcinoma, and adenoma were excluded. Difficult lesions were defined as ESD requiring a long procedure time (≥120 min), perforation development, piecemeal resection, or discontinued ESD. In the present study, the clinical factors were assessed to identify the technical difficulty of ESD using univariate and multivariate analyses. RESULTS: Among 1708 lesions treated with esophageal ESD, eight subepithelial tumors, 44 adenocarcinomas, and two adenomas were excluded. Finally, 1505 patients with 1654 lesions were analyzed, and 217 patients with 217 lesions (13.1%) were classified as patients with difficult lesions. In multivariate analysis, the predictive factors associated with the technical difficulty of ESD were as follows: tumors with varices, tumors with diverticulum, antiplatelet use (discontinued), circumference of tumor (≥1/2), preoperative tumor size ≥30 mm, trainee, and nonhigh-volume center. CONCLUSION: This multicenter retrospective study identified the predictive factors associated with the technical difficulty of ESD for ESCC with varied backgrounds and factors.

Long-Term Outcomes of Endoscopic Submucosal Dissection for Early Remnant Gastric Cancer: A Retrospective Multicenter Study.

INTRODUCTION: Favorable long-term outcomes of endoscopic submucosal dissection (ESD) for early remnant gastric cancer (ERGC) have been reported in single-center studies from advanced institutions. However, no studies have examined the long-term outcomes using a multicenter database. This study aimed to investigate the long-term outcomes of the aforementioned approach using a large multicenter database. METHODS: This retrospective multicenter cohort study included 242 cases with 256 lesions that underwent ESD for ERGC between April 2009 and March 2019 across 12 centers. We investigated the long-term outcomes of these patients with the Kaplan-Meier method, and the relationship between curability, additional treatment, or hospital category, and the survival time was evaluated using the log-rank test. RESULTS: During the median follow-up period of 48.4 months, the 5-year overall survival rate was 81.3%, and the 5-year gastric cancer-specific survival rate was 98.1%. The survival time of patients of endoscopic curability (eCura) C-2 without additional surgery was significantly shorter than the corresponding of patients of eCura A/B/C-1 and eCura C-2 with additional surgery. There was no significant difference in either overall survival or gastric cancer-specific survival rate between the high-volume and non-high-volume hospitals. CONCLUSION: The gastric cancer-specific survival of ESD for ERGC using a multicenter database was favorable. ESD for ERGC is widely applicable regardless of the hospital case volume. Management in accordance with the latest guidelines will lead to long-term survival.

Clinical Guidelines for Diagnosis and Management of Peutz-Jeghers Syndrome in Children and Adults.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare disease characterized by the presence of hamartomatous polyposis throughout the gastrointestinal tract, except for the esophagus, along with characteristic mucocutaneous pigmentation. It is caused by germline pathogenic variants of the STK11 gene, which exhibit an autosomal dominant mode of inheritance. Some patients with PJS develop gastrointestinal lesions in childhood and require continuous medical care until adulthood and sometimes have serious complications that significantly reduce their quality of life. Hamartomatous polyps in the small bowel may cause bleeding, intestinal obstruction, and intussusception. Novel diagnostic and therapeutic endoscopic procedures such as small-bowel capsule endoscopy and balloon-assisted enteroscopy have been developed in recent years. SUMMARY: Under these circumstances, there is growing concern about the management of PJS in Japan, and there are no practice guidelines available. To address this situation, the guideline committee was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labour and Welfare with specialists from multiple academic societies. The present clinical guidelines explain the principles in the diagnosis and management of PJS together with four clinical questions and corresponding recommendations based on a careful review of the evidence and involved incorporating the concept of the Grading of Recommendations Assessment, Development and Evaluation system. KEY MESSAGES: Herein, we present the English version of the clinical practice guidelines of PJS to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with PJS.

A Multicenter Prospective Validation Study on Selective Endoscopic Resection of Sessile Serrated Lesions Using Magnifying Colonoscopy in Clinical Practice.

INTRODUCTION: Sessile serrated lesions (SSLs) have malignant potential for colorectal cancer in the serrated pathway. Selective endoscopic resection of SSLs would reduce medical costs and procedure-related accidents, but the accurate endoscopic differentiation of SSLs from hyperplastic polyps (HPs) is challenging. To explore the differential diagnostic performance of magnifying colonoscopy in distinguishing SSLs from HPs, we conducted a multicenter prospective validation study in clinical practice. METHODS: Considering the rarity of diminutive SSLs, all lesions ≥6 mm that were detected during colonoscopy and diagnosed as type 1 based on the Japan narrow-band imaging expert team (JNET) classification were included in this study. Twenty expert endoscopists were asked to differentiate between SSLs and HPs with high or low confidence level after conventional and magnifying NBI observation. To examine the validity of selective endoscopic resection of SSLs using magnifying colonoscopy in clinical practice, we calculated the sensitivity of endoscopic diagnosis of SSLs with histopathological findings as comparable reference. RESULTS: A total of 217 JNET type 1 lesions from 162 patients were analyzed, and 114 lesions were diagnosed with high confidence. The sensitivity of magnifying colonoscopy in detecting SSLs was 79.8% (95% confidence interval [CI]: 74.7-84.4%) overall, and 82.4% (95% CI: 76.1-87.7%) in the high-confidence group. These results showed that the sensitivity of this study was not high enough, even limited in the high-confidence group. CONCLUSIONS: Accurate differential diagnosis of SSLs and HPs using magnifying colonoscopy was challenging even for experts. JNET type 1 lesions ≥6 mm are recommended to be resected because selective endoscopic resection has a disadvantage of leaving approximately 20% of SSLs on site.

Intensive endoscopic resection for downstaging of polyp burden in patients with familial adenomatous polyposis (J-FAPP Study III): a multicenter prospective interventional study.

BACKGROUND: Total colectomy is the standard treatment for familial adenomatous polyposis (FAP). Recently, an increasing number of young patients with FAP have requested the postponement of surgery or have refused to undergo surgery. We aimed to evaluate the effectiveness of intensive endoscopic removal for downstaging of polyp burden (IDP) in FAP. METHOD: A single-arm intervention study was conducted at 22 facilities. Participants were patients with FAP, aged ≥ 16 years, who had not undergone colectomy or who had undergone colectomy but had ≥ 10 cm of large intestine remaining. For IDP, colorectal polyps of ≥ 10 mm were removed, followed by polyps of ≥ 5 mm. The primary end point was the presence/absence of colectomy during a 5-year intervention period. RESULTS: 222 patients were eligible, of whom 166 had not undergone colectomy, 46 had undergone subtotal colectomy with ileorectal anastomosis, and 10 had undergone partial resection of the large intestine. During the intervention period, five patients (2.3 %, 95 % confidence interval [CI] 0.74 %-5.18 %) underwent colectomy, and three patients died. Completion of the 5-year intervention period without colectomy was confirmed in 150 /166 patients who had not undergone colectomy (90.4 %, 95 %CI 84.8 %-94.4 %) and in 47 /56 patients who had previously undergone colectomy (83.9 %, 95 %CI 71.7 %-92.4 %). CONCLUSION: IDP in patients with mild-to-moderate FAP could have the potential to be a useful means of preventing colorectal cancer without implementing colectomy. However, if the IDP protocol was proposed during a much longer term, it may not preclude the possibility that a large proportion of colectomies may still need to be performed.

Telementoring for endoscopic submucosal dissection in vivo training.

The provision of endoscopic training was significantly disrupted during the coronavirus disease (COVID-19) pandemic. It is difficult to provide training on endoscopic submucosal dissection (ESD) due to the complexity of the procedure and the shortage of local trainers. We have designed and conducted a simulation training course with telementoring, incorporating the concept of rapid cycle deliberate practice (RCDP). After a short tutorial on basic setup and maneuvering, the participants undergo 2 h of training on a live anesthetized pig to acquire the necessary skills for ESD. Two overseas experts were involved virtually in real time as telementors. A video camera was set up at each station, and both external and endoscopic views were transmitted live between the animal laboratory and telementors via the Zoom application. The overseas experts actively engaged in the simulation by giving live feedback and instructions to participants using visual aids supported by the meeting application. The training model utilized the concept of RCDP, where repeated immediate feedback and discussion would be carried out to enhance the efficiency of learning. Eighteen trainees were invited to participate in the course, six of them instructed by overseas telementors. Four ESD procedures were performed by participants under telementoring and achieved 100% en bloc resection without perforation. The times required for each ESD were similar with telementoring than that of on-site mentors. The establishment of telementoring has enabled knowledge and skill transfer of complex endoscopic procedures of ESD. With the limitations of international travel, this could be an alternative model allowing remote training, particularly when local experts are not readily available.

Updates in narrow-band imaging for colorectal polyps: Narrow-band imaging generations, detection, diagnosis, and artificial intelligence.

Narrow-band imaging (NBI) is an optical digital enhancement method that allows the observation of vascular and surface structures of colorectal lesions. Its usefulness in the detection and diagnosis of colorectal polyps has been demonstrated in several clinical trials and the diagnostic algorithms have been simplified after the establishment of endoscopic classifications such as the Japan NBI Expert Team classification. However, there were issues including lack of brightness in the earlier models, poor visibility under insufficient bowel preparation, and the incompatibility of magnifying endoscopes in certain endoscopic platforms, which had impeded NBI from becoming standardized globally. Nonetheless, NBI continued its evolution and the newest endoscopic platform launched in 2020 offers significantly brighter and detailed images. Enhanced visualization is expected to improve the detection of polyps while universal compatibility across all scopes including magnifying endoscopy will promote the global standardization of magnifying diagnosis. Therefore, knowledge related to magnifying colonoscopy will become essential as magnification becomes standardly equipped in future models, although the advent of computer-aided diagnosis and detection may greatly assist endoscopists to ensure quality of practice. Given that most endoscopic departments will be using both old and new models, it is important to understand how each generation of endoscopic platforms differ from each other. We reviewed the advances in the endoscopic platforms, artificial intelligence, and evidence related to NBI essential for the next generation of endoscopic practice.

New application of endocytoscope for histopathological diagnosis of colorectal lesions.

BACKGROUND: The endocytoscope with ultra-high magnification (x 520) allows us to observe the cellular structure of the colon epithelium during colonoscopy, known as virtual histopathology. We hypothesized that the endocytoscope could directly observe colorectal histopathological specimens and store them as endocyto-pathological images by the endoscopists without a microscope, potentially saving the burden on histopathologists. AIM: To assess the feasibility of endocyto-pathological images taken by an endoscopist as adequate materials for histopathological diagnosis. METHODS: Three gastrointestinal pathologists were invited and asked to diagnose 40 cases of endocyto-pathological images of colorectal specimens. Each case contained seven endocyto-pathological images taken by an endoscopist, consisting of one loupe image, three low-magnification images, and three ultra-high magnification images. The participants chose hyperplastic polyp or low-grade adenoma for 20 cases of endocyto-pathological images (10 hyperplastic polyps, and 10 Low-grade adenomas in conventional histopathology) in study 1 and high-grade adenoma/ shallow invasive cancer or deep invasive cancer for 20 cases [10 tumor in situ/T1a and 10 T1b] in study 2. We investigated the agreement between the histopathological diagnosis using the endocyto-pathological images and conventional histopathological diagnosis. RESULTS: Agreement between the endocyto-pathological and conventional histopathological diagnosis by the three gastrointestinal pathologists was 100% (95%CI: 94.0%-100%) in studies 1 and 2. The interobserver agreement among the three gastrointestinal pathologists was 100%, and the κ coefficient was 1.00 in both studies. CONCLUSION: Endocyto-pathological images were adequate and reliable materials for histopathological diagnosis.

Aspirin-Mediated Prevention of Colorectal Adenomas Recurrence is Affected by Blood Biochemistry and Nutritional Intake.

Aspirin has been shown to prevent the onset of colorectal adenoma and cancer. This study aimed to identify patient characteristics and blood chemistry factors related to the effect of aspirin. A total of 231 men and 59 women who participated in our previous randomized clinical study in 2007-2009 using aspirin or placebo (J-CAPP study) were analyzed. Interaction of aspirin with age at entry, body mass index (BMI), alcohol intake, blood biochemistry, and nutrients calculated from a semiquantitative food frequency questionnaire were analyzed on the basis of the presence of adenomas 2 years later. Our study showed that suppression of adenoma by aspirin was not affected by age or BMI. Among men, significant suppression of adenoma by aspirin was seen with triglyceride (TG) <167 mg/dL (P = 0.02), total cholesterol (T-cho) ≥220 mg/dL (P = 0.01), high-density lipoprotein (HDL) ≥60 mg/dL (P < 0.01), and low-density lipoprotein (LDL) ≥140 mg/dL (P = 0.01), aspartate aminotransferase (AST) <30 IU/L (P = 0.01), alanine aminotransferase <30 IU/L (P = 0.04), and gamma-glutamyl transpeptidase <60 IU/L (P = 0.04). In addition, the interaction was significant with TG ≥/<167 mg/dL (P = 0.02), T-cho ≥/<220 mg/dL (P = 0.03), HDL ≥/<60 mg/dL (P = 0.02), LDL ≥/<140 mg/dL (P = 0.03), and AST ≥/<30 IU/L (P = 0.01). Daily nutrient intake associated with aspirin was <2,000 mg sodium (P = 0.06) and ≥850 µg retinol equivalent (P = 0.05) among men, indicating a marginal effect on adenoma suppression. No significant differences were detected among women due to the small sample size. In conclusion, lipid metabolism and liver function were correlated with the suppressive effect of aspirin on the recurrence of colorectal adenoma. PREVENTION RELEVANCE: Aspirin has been shown to prevent the onset of colorectal adenoma and cancer, and its effect modifications have been analyzed. Lipid metabolism and liver function were correlated with the suppressive effect of aspirin on the recurrence of colorectal adenoma.

Ultrasonic cleaning is effective in removing carbonized clots and tissue from the insulation-tipped diathermic knife-2.

Objectives: Since carbonized clots and tissue (debris) tend to adhere firmly to the tip of the endoscopic submucosal dissection (ESD) knife as the procedure proceeds, manual removing the firm debris is often challenging and time-consuming. Recently, effective ultrasonic cleaning for other medical devices has been reported. The aim of the present study was to clarify whether ultrasonic cleaning is effective in removing the debris on the insulation-tipped diathermic (IT) knife-2. Methods: This study was an ex-vivo experimental randomized study. A total of 40 IT knife-2 knives with debris on their tip surfaces were prepared and randomly assigned to two groups (Group A and Group B). The knives in Group A were cleaned using the conventional scrubbing method for 30 s (conventional cleaning method), while those in Group B were cleaned using a combined method of scrubbing for 20 s and ultrasonic cleaning for 10 s (combined ultrasonic cleaning method). The tip electrode of the knife after cleaning was photographed under a microscope (40x). The 40 images of the knives were evaluated by independent three endoscopists and two clinical engineers using the five-step evaluation criteria ranging from cleaning score 1 (dirty) to 5 (clean). Results: The mean cleaning score of 3.78 (range: 2.33-4.67) in Group B was significantly higher than that of 1.68 (range: 1.00-2.83) in Group A. Conclusions: The combined ultrasonic cleaning method could remove debris adhering to the IT knife-2 more effectively than the conventional cleaning method. Ultrasonic cleaning may be applied for real-world ESD.

Characteristics of colorectal neuroendocrine tumors in patients prospectively enrolled in a Japanese multicenter study: a first report from the C-NET STUDY.

BACKGROUND: This is the first report from a multicenter prospective cohort study of colorectal neuroendocrine tumor (NET), the C-NET STUDY, conducted to assess the long-term outcomes of the enrolled patients. This report aimed to elucidate the clinicopathological features of the enrolled patients and lesions. METHODS: Colorectal NET patients aged 20-74 years were consecutively enrolled and followed up at 50 institutions. The baseline characteristics and clinicopathological findings at enrollment and treatment were assessed. RESULTS: A total of 495 patients with 500 colorectal NETs were included. The median patient age was 54 years, and 85.3% were asymptomatic. The most frequent lesion location was the lower rectum (88.0%); 99.4% of the lesions were clinically diagnosed to be devoid of metastatic findings, and 95.4% were treated with endoscopic resection. Lesions < 10 mm comprised 87.0% of the total, 96.6% had not invaded the muscularis propria, and 92.6% were classified as WHO NET grade 1. Positive lymphovascular involvement was found in 29.2% of the lesions. Its prevalence was high even in small NETs with immunohistochemical/special staining for pathological assessment (26.4% and 40.9% in lesions sized < 5 mm and 5-9 mm, respectively). Among 70 patients who underwent radical surgery primarily or secondarily, 18 showed positive lymph node metastasis. CONCLUSIONS: The characteristics of real-world colorectal NET patients and lesions are elucidated. The high positivity of lymphovascular involvement in small NETs highlights the necessity of assessing the clinical significance of positive lymphovascular involvement based on long-term outcomes, which will be examined in later stages of the C-NET STUDY. TRIAL REGISTRATION NUMBER: UMIN000025215.

Efficacy of international web-based educational intervention in the detection of high-risk flat and depressed colorectal lesions higher (CATCH project) with a video: Randomized trial.

OBJECTIVES: Three subcategories of high-risk flat and depressed lesions (FDLs), laterally spreading tumors non-granular type (LST-NG), depressed lesions, and large sessile serrated lesions (SSLs), are highly attributable to post-colonoscopy colorectal cancer (CRC). Efficient and organized educational programs on detecting high-risk FDLs are lacking. We aimed to explore whether a web-based educational intervention with training on FIND clues (fold deformation, intensive stool/mucus attachment, no vessel visibility, and demarcated reddish area) may improve the ability to detect high-risk FDLs. METHODS: This was an international web-based randomized control trial that enrolled non-expert endoscopists in 13 Asian countries. The participants were randomized into either education or non-education group. All participants took the pre-test and post-test to read 60 endoscopic images (40 high-risk FDLs, five polypoid, 15 no lesions) and answered whether there was a lesion. Only the education group received a self-education program (video and training questions and answers) between the tests. The primary outcome was a detection rate of high-risk FDLs. RESULTS: In total, 284 participants were randomized. After excluding non-responders, the final data analyses were based on 139 participants in the education group and 130 in the non-education group. The detection rate of high-risk FDLs in the education group significantly improved by 14.7% (66.6-81.3%) compared with -0.8% (70.8-70.0%) in the non-education group. Similarly, the detection rate of LST-NG, depressed lesions, and large SSLs significantly increased only in the education group by 12.7%, 12.0%, and 21.6%, respectively. CONCLUSION: Short self-education focusing on detecting high-risk FDLs was effective for Asian non-expert endoscopists. (UMIN000042348).