Acute Gastropathy Associated with Bowel Preparation According to Age: Oral Sulfate Tablets versus 1-L Polyethylene Glycol with Ascorbic Acid.

Background/Aims: The use of 1-L polyethylene glycol with ascorbate (PEG/Asc) and oral sulfate tablets (OST) as low-volume bowel preparation agents has gradually increased. However, these agents may induce acute gastropathy during bowel preparation, particularly in elderly populations. This study aimed to compare the incidence of acute gastropathy of 1-L PEG/Asc and OST according to age, as well as efficacy and safety. Methods: This retrospective study included patients who underwent esophagogastroduodenoscopy (EGD) and colonoscopy for screening on the same day and underwent bowel preparation using OST or 1-L PEG/Asc. We collected EGD findings related to acute gastropathy, bowel-cleansing score using the Boston Bowel Preparation Scale (BBPS), polyp or adenoma detection rate (ADR), and laboratory parameters. Results: Of 4,711 patients, 1,758, 2,241, and 712 were in the younger (18-49 years), middle-aged (50-64 years), and older (≥65 years) groups, respectively. In all age groups, the OST group had higher rates of acute gastropathy than the 1-L PEG/Asc group. The younger-, middle-, and older-aged groups had OST and 1-L PEG/Asc usage rates of 42.9% and 11.6%, 41.2% and 16.0%, and 41.5% and 16.4%, respectively. Notably, in the younger group, the total BBPS and ADR scores were significantly higher in the OST group than in the 1-L PEG/Asc group; however, these did not differ in the other age groups. Conclusions: Acute gastropathy was more strongly associated with OST than with 1-L PEG/Asc in all age groups. Therefore, physicians should consider acute gastropathy associated with low-volume agents in all age groups when performing bowel preparation.

Acute Gastropathy Associated with Bowel Preparation for Colonoscopy.

Background/Aims: Utilization of low-volume preparation agents is crucial to improve patient willingness to undergo repeat colonoscopies. However, gastric safety data on preparation agents are limited. This study evaluated the acute gastropathy associated with bowel preparation agents. Methods: This retrospective study enrolled healthy subjects who underwent both esophagogastroduodenoscopy and colonoscopy screening. Baseline patient characteristics, bowel preparation success, acute gastropathy, and polyp and adenoma detection rates were evaluated for 1 L polyethylene glycol with ascorbic acid (1 L PEG/Asc) and oral sulfate tablet (OST) groups. Results: Comparison of the OST group (n=2,463) with the 1 L PEG/Asc group (n=2,060) revealed that the rates of successful cleansing and high-quality cleansing were similar between the two groups. Polyp and adenoma detection rates were significantly higher in the OST group than in the 1 L PEG/Asc group (p<0.001 and p=0.013), while the incidence of acute gastric mucosal lesion-like blood stain/clot, erosions at greater curvature side of antrum/body, multiple erosions, and overlying mucosal erythema or edema were all significantly higher in the OST group than in the 1 L PEG/Asc group (all p<0.001). Additionally, high and indeterminate probability scores of preparation agent-induced gastropathy (p=0.001) and mean Lanza scores were significantly higher in the OST group than in the 1 L PEG/Asc group (1.3 vs. 0.4, p<0.001). Conclusions: Compared with 1 L PEG/Asc, OSTs were significantly associated with acute gastropathy during bowel preparation, thus requiring careful consideration from physicians for the simultaneous screening of EGD and colonoscopy.

Demographic Characteristics and Economic Burden of Clostridioides difficile Infection in Korea: A Nationwide Population-Based Study after Propensity Score Matching.

Clostridioides difficile infection (CDI) poses a considerable threat to global public health. However, there have been insufficient propensity score-matched data on its demographic characteristics and economic burden. Using nationwide claims data, we assessed longitudinal changes in the demographic characteristics and economic burden of CDI between 2011 and 2019 after propensity score matching. We performed a regression analysis to compare the differences in the length of hospital stay and medical costs between patients with CDI and controls (gastroenteritis and colitis). The CDI hospitalization rate increased 2.9-fold between 2011 and 2019. The CDI group had higher comorbidity index scores and was more frequently diagnosed at tertiary hospitals and in the Seoul region than the control group (all p < 0.001). The annual incidence rate of CDI/10,000 persons significantly increased in both sexes and all age groups. The length of hospital stay and medical costs were 3.3-fold and 5.0-fold greater, respectively, in the CDI than in the control group (both p < 0.001). Although the length of hospital stay decreased, total medical costs increased in all age groups and both sexes between 2011 and 2019 (all p < 0.001). When compared with the control group, the CDI-attributable length of hospital stay and medical cost were greater by 15.3 days and KRW 3413 (×103), respectively, after matching. In conclusion, CDI incidence, particularly among the elderly population with comorbidities, has been increasing. In addition, the length of hospital stay and total medical costs of the CDI group were greater than those of the control group.

A survey of current practices in post-polypectomy surveillance in Korea.

BACKGROUND/AIMS: We investigated the clinical practice patterns of post-polypectomy colonoscopic surveillance among Korean endoscopists. METHODS: In a web-based survey conducted between September and November 2021, participants were asked about their preferred surveillance intervals and the patient age at which surveillance was discontinued. Adherence to the recent guidelines of the U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) was also analyzed. RESULTS: In total, 196 endoscopists completed the survey. The most preferred first surveillance intervals were: a 5-year interval after the removal of 1-2 tubular adenomas < 10 mm; a 3-year interval after the removal of 3-10 tubular adenomas < 10 mm, adenomas ≥ 10 mm, tubulovillous or villous adenomas, ≤ 20 hyperplastic polyps < 10 mm, 1-4 sessile serrated lesions (SSLs) < 10 mm, hyperplastic polyps or SSLs ≥ 10 mm, and traditional serrated adenomas; and a 1-year interval after the removal of adenomas with highgrade dysplasia, >10 adenomas, 5-10 SSLs, and SSLs with dysplasia. In piecemeal resections of large polyps ( > 20 mm), surveillance colonoscopy was mostly preferred after 1 year for adenomas and 6 months for SSLs. The mean USMSTF guideline adherence rate was 30.7%. The largest proportion of respondents (40.8%-55.1%) discontinued the surveillance at the patient age of 80-84 years. CONCLUSIONS: A significant discrepancy was observed between the preferred post-polypectomy surveillance intervals and recent international guidelines. Individualized measures are required to increase adherence to the guidelines.

Impact of COVID-19 Pandemic on Performance of Gastrointestinal Endoscopy.

Background/Aims: Non-time-sensitive gastrointestinal endoscopy was deferred because of the risk of exposure to coronavirus disease 2019 (COVID-19), but no population-based studies have quantified the adverse impact on gastrointestinal procedures. This study examined the impact of the COVID-19 pandemic on the performance of esophagogastroduodenoscopy (EGD), colonoscopy, ERCP, and abdominal ultrasonography (US) in South Korea. Methods: This nationwide, population-based study compared the claim data of EGD, colonoscopy, ERCP, and abdominal US in 2020 and 2021 (COVID-19 era) with those in 2019 (before the COVID-19 era). Results: During the first year (2020) of the COVID-19 pandemic, the annual claim data of EGD and colonoscopy were reduced by 6.3% and 6.9%, respectively, but those of ERCP and abdominal US were increased by 1.0% and 2.9%, compared to those in 2019. During the first surge (March and April 2020) of COVID-19, the monthly claim data of EGD, colonoscopy, ERCP, and abdominal US were reduced by 28.8%, 43.8%, 5.1%, and 21.6%, respectively, in March 2020, and also reduced by 17.2%, 32.8%, 4.4%, and 9.5%, respectively, in April 2020, compared to those in March and April 2019. During March and April 2020, the monthly claims of ERCP, compared with those in 2019, declined less significantly than those of EGD and colonoscopy (both p<0.001). Conclusions: The claims of EGD and colonoscopy were reduced more significantly than those of ERCP and abdominal US during the COVID-19 pandemic because ERCPs are time-sensitive procedures and abdominal USs are non-aerosolized procedures.

Single-Cell Network-Based Drug Repositioning for Discovery of Therapies against Anti-Tumour Necrosis Factor-Resistant Crohn's Disease.

Primary and secondary non-response affects approximately 50% of patients with Crohn's disease treated with anti-tumour necrosis factor (TNF) monoclonal antibodies. To date, very little single cell research exists regarding drug repurposing in Crohn's disease. We aimed to elucidate the cellular phenomena underlying resistance to anti-TNF therapy in patients with Crohn's disease and to identify potential drug candidates for these patients. Single-cell transcriptome analyses were performed using data (GSE134809) from the Gene Expression Omnibus and Library of Integrated Network-Based Cellular Signatures L1000 Project. Data aligned to the Genome Reference Consortium Human Build 38 reference genome using the Cell Ranger software were processed using the Seurat package. To capture significant functional terms, gene ontology functional enrichment analysis was performed on the marker genes. For biological analysis, 93,893 cells were retained (median 20,163 genes). Through marker genes, seven major cell lineages were identified: B-cells, T-cells, natural killer cells, monocytes, endothelial cells, epithelial cells, and tissue stem cells. In the anti-TNF-resistant samples, the top 10 differentially expressed genes were HLA-DQB-1, IGHG1, RPS23, RPL7A, ARID5B, LTB, STAT1, NAMPT, COTL1, ISG20, IGHA1, IGKC, and JCHAIN, which were robustly distributed in all cell lineages, mainly in B-cells. Through molecular function analyses, we found that the biological functions of both monocyte and T-cell groups mainly involved immune-mediated functions. According to multi-cluster drug repurposing prediction, vorinostat is the top drug candidate for patients with anti-TNF-refractory Crohn's disease. Differences in cell populations and immune-related activity within tissues may influence the responsiveness of Crohn's disease to anti-TNF agents. Vorinostat may serve as a promising novel therapy for anti-TNF-resistant Crohn's disease.

The elderly population are more vulnerable for the management of colorectal cancer during the COVID-19 pandemic: a nationwide, population-based study.

BACKGROUND/AIMS: The impact of coronavirus disease 2019 (COVID-19) on the management of colorectal cancer (CRC) may worse in elderly population, as almost all COVID-19 deaths occurred in the elderly patients. This study aimed to evaluate the impact of COVID-19 on CRC management in the elderly population. METHODS: The numbers of patients who underwent colonoscopy, who visited hospitals or operated for CRC in 2020 and 2021 (COVID-19 era) were compared with those in 2019, according to 3 age groups (≥70 years, 50-69 years, and ≤49 years), based on the nationwide, population-based database (2019-2021) in South Korea. RESULTS: The annual volumes of colonoscopy and hospital visits for CRC in 2020 were more significantly declined in the old age group than in the young age group (both P<0.001). In addition, the annual volume of patients operated for CRC numerically more declined in old age group than in young age group. During the first surge of COVID-19 (March and April 2020), old age patients showed statistically significant declines for the monthly number of colonoscopies (-46.5% vs. -39.3%, P<0.001), hospital visits (-15.4% vs. -7.9%, P<0.001), CRC operations (-33.8% vs. -0.7%, P<0.05), and colonoscopic polypectomies (-41.8% vs. -38.0%, P<0.001) than young age patients, compared with those of same months in 2019. CONCLUSIONS: Elderly population are more vulnerable for the management of CRC during the COVID-19 pandemic. Therefore, the elderly population are more carefully cared for in the management of CRC during the next pandemic.

Impact of the COVID-19 Pandemic on Esophagogastroduodenoscopy and Gastric Cancer Claims in South Korea: A Nationwide, Population-Based Study.

PURPOSE: There has been little information about the impact of coronavirus disease 2019 (COVID-19) pandemic on esophagogastroduodenoscopy (EGD) and gastric cancer claims. This study aimed to measure the impact of COVID-19 pandemic on EGD and gastric cancer claims in South Korea. MATERIALS AND METHODS: This nationwide, population-based study compared the claims data of EGD, gastric cancer, early gastric cancer (EGC), advanced gastric cancer (AGC) and gastric cancer operation in 2020 and 2021 (COVID-19 era) to those in 2019 (before COVID-19 pandemic). RESULTS: The annual claims of EGD, gastric cancer, EGC, and AGC were reduced by 6.3%, 5.0%, 4.7%, and 3.6% in 2020 and by 2.2%, 1.0%, 0.6%, and 1.9% in 2021, respectively, compared to 2019. The amount of annual claims of gastric cancer operation was reduced by 8.8% in 2020, but increased by 0.9% in 2021, compared to those in 2019. The monthly claims of EGD, gastric cancer, EGC, AGC, and gastric cancer operation were mainly reduced in the first epidemic wave of COVID-19, but decreased in the 2nd to 4th epidemic wave. Compared to 2019, the monthly claim of EGD, gastric cancer, EGC, AGC, and gastric cancer operation were reduced by 28.8%, 14.3%, 18.1%, 9.2%, and 5.8% in March 2020 and by 17.2%, 10.8%, 10.3%, 7.2%, and 35.4% in April 2020, respectively. CONCLUSION: Negative impact of the COVID-19 pandemic on EGD, gastric cancer, EGC, AGC, and gastric cancer operation was worst during the first surge of COVID-19, but decreased in the 2nd to 4th epidemic wave of the disease in 2020 and 2021.

Clinical and pathological characteristics of early-onset colorectal cancer in South Korea.

Background: Early-onset colorectal cancer (EOCRC) may differ by race and ethnicity, and recently South Korea has witnessed a surge in cases. We aimed to evaluate the clinical and pathological features of patients with EOCRC, and to determine the predictors of overall survival. Methods: In this retrospective study, EOCRC was defined as CRC diagnosed in patients aged < 50 years, and late-onset CRC was defined as CRC diagnosed in those over 75 years of age. The clinical and pathological characteristics of patients with EOCRC were compared with late-onset CRC. We also used multivariable Cox proportional hazard models to find predictors of overall survival in patients with EOCRC. Results: The proportion of early-onset CRC was 9.1% of 518 patients with CRC, and the clinical and pathological characteristics were similar between early-onset (n = 47) and late-onset CRC (n = 134). However, EOCRC had a preponderance for distal tumor location (70.2% vs. 50.7%, P = 0.02) and T1-2 stage disease (23.4% vs. 11.2%, P = 0.04), compared with those of late-onset CRC. Using multivariable Cox proportional hazard models, only vascular invasion (hazard ratio = 8.75, 95% confidence interval 1.139‒67.197) was found to be a risk factor for overall survival (P = 0.04) for patients with CRC. Conclusion: EOCRC had preponderance for distal tumor location and early T-stage disease, compared with late-onset CRC. Considering the increasing incidence of EOCRC, more studies on clinical and pathological characteristics of EOCRC may be warranted.

Neutrophil to lymphocyte ratio can predict overall survival in patients with stage II to III colorectal cancer.

The neutrophil-to-lymphocyte ratio (NLR) is a prognostic inflammatory marker in colorectal cancer (CRC), however, little is known for its prognostic role in stage II to III CRC patients underwent curative resection. This study was aimed to investigate prognostic role of NLR in stage II to III CRC patients underwent surgery. Medical records of 1378 newly diagnosed CRC patients between June 2006 and March 2020 were reviewed. Data were collected by using electronic medical record software. Survival rate were analyzed using the Kaplan-Meier method. The cutoff values of NLR in stage II to III CRC patients were defined by maximally selected log-rank statistics. Multivariable cox proportional-hazard models were performed to find risk factors associated with overall survival (OS) in stage II to III CRC patients underwent surgery. Among 1378 CRC patients enrolled, 910 patients underwent surgery. In entire surgical cohort, age, body mass index (BMI), CEA, carbohydrate antigen 19-9 (CA 19-9), lymphatic invasion, NLR, and albumin-to-globulin ratio (AGR) were found to be risk factors associated with OS (all P < .05). In stage II to III CRC patients underwent curative resection (n = 623), age, BMI, lymphatic invasion, AGR, and NLR were found to be risk factors associated with OS (all P < .05). In the multivariable analysis, CA 19-9 and lymphatic invasion were independent risk factors for OS in entire surgical cohort. In the multivariable analysis for the stage II to III CRC patients, age, BMI, lymphatic invasion and NLR (Hazard ratio = 2.41, 95% confidential interval [CI]: 1.04-5.595, P = .041) were independent risk factors for OS. NLR can be used as a clinically simple and useful parameter for predicting OS in stage II to III CRC patients undergoing curative resection, however, its optimal cutoff value should be further evaluated.

Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 revised edition.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: adenoma ≥10 mm in size; 3 to 5 (or more) adenomas; tubulovillous or villous adenoma; adenoma containing high-grade dysplasia; traditional serrated adenoma; sessile serrated lesion containing any grade of dysplasia; serrated polyp of at least 10 mm in size; and 3 to 5 (or more) sessile serrated lesions. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Chasm between Public Perceptions and Epidemiological Data on Colorectal Cancer.

Background/Aims: Only a few studies have examined perceptions of the incidence and prognosis of colorectal cancer (CRC) in the general Korean population. The aim of this study was to determine public perceptions of the lifetime incidence rate and survival of CRC. Methods: All adults older than 50 years who visited the Kyung Hee University Hospital at Gangdong were invited to participate in this survey for 5 months in 2021. During the study period, eligible individuals participated in this survey through a link or quick response code on a poster posted in the hospital, which was linked to a web-based questionnaire. The questionnaire used for this survey included demographic and socioeconomic data, perceptions of CRC, and awareness of the CRC incidence and 5-year survival rate. Results: Among 203 respondents, 196 answers were analyzed after the exclusion of seven incomplete answers. In our survey, half of the respondents (49.5%) answered the expected lifetime incidence rate of CRC as 0% to 4.9%. Koreans perceived CRC as a more fatal disease than epidemiological data, as 70.9% of the respondents expected the 5-year survival rate of CRC to be less than 70% for the general population. However, Koreans perceived stage IV CRC as a less fatal disease than epidemiological data, because only 20.9% of the respondents expected the 5-year survival rate of stage IV CRC to be less than 10% for general population. Conclusions: Koreans recognized CRC as a more common and fatal disease than actual epidemiological data of CRC. Therefore, more efforts should be made to provide more correct information on CRC for better decision-making and communication.

Korean guidelines for postpolypectomy colonoscopic surveillance: 2022 revised edition.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for the management of advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: (1) adenoma ≥10 mm in size; (2) 3 to 5 (or more) adenomas; (3) tubulovillous or villous adenoma; (4) adenoma containing high-grade dysplasia; (5) traditional serrated adenoma; (6) sessile serrated lesion (SSL) containing any grade of dysplasia; (7) serrated polyp of at least 10 mm in size; and (8) 3 to 5 (or more) SSLs. More studies are needed to fully comprehend the patients most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

[Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 Revised Edition].

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: 1) adenoma ≥10 mm in size; 2) 3-5 (or more) adenomas; 3) tubulovillous or villous adenoma; 4) adenoma containing high-grade dysplasia; 5) traditional serrated adenoma; 6) sessile serrated lesion (SSL) containing any grade of dysplasia; 7) serrated polyp of at least 10 mm in size; and 8) 3-5 (or more) SSLs. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Gastrointestinal and non-gastrointestinal complication rates associated with diagnostic esophagogastroduodenoscopy under sedation.

ABSTRACT: Esophagogastroduodenoscopy (EGD) under sedation may result in gastrointestinal (GI) and non-GI complications. However, no previous studies have reported 30-day GI and non-GI complications after diagnostic EGD under sedation.We conducted a retrospective, observational study of 30-day GI and non-GI complication rates after outpatient diagnostic EGD under sedation in subjects ≥18 years between January 2012 and December 2017 based on a common data model database. Thirty-day complication rates were compared with EGD under sedation or not, type of sedation drugs (midazolam only vs midazolam/propofol) and age groups (18-64 year vs ≥65 year) for GI (bleeding and perforation) and non-GI complications (pneumonia, acute myocardial infarction, congestive heart failure and cerebral stroke).In total, 39,910 were performed with sedation (midazolam only, n = 16,033 and midazolam/propofol, n = 23,864) and 22,894 were performed without sedation. Elderly patients significantly favored EGD without sedation (P < .01). GI and non-GI complication rates were similar between EGD under sedation and without sedation (all P > .1) except for acute myocardial infarction rate, which was significantly higher in EGD without sedation than EGD under sedation (1.7/10,000 vs 0.3/10,000 persons, P = .043). All GI and non-GI complications were also similar between the midazolam/propofol and midazolam only groups as well as between young and old patients (all P > .1).Outpatient diagnostic EGD under sedation has an excellent safety profile. In addition, it can be safely performed with midazolam only or midazolam/propofol and in young and old patients.

Uncovering Novel Pre-Treatment Molecular Biomarkers for Anti-TNF Therapeutic Response in Patients with Crohn's Disease.

Neutralising monoclonal antibodies for tumour necrosis factor (TNF) has been widely used to treat Crohn's disease (CD) in clinical practice. However, differential individual response necessitates a therapeutic response assessment of anti-TNF agents in CD patients for optimizing therapeutic strategy. We aimed to predict anti-TNF therapy response in CD patients using transcriptome analyses. Transcriptome analyses were performed using data from the Gene Expression Omnibus, GeneCards, and Human Protein Atlas databases. The significantly mitigated biological functions associated with anti-TNF therapy resistance in CD patients encompassed immune pathways, including Interleukin-17 (IL-17) signaling, cytokine-cytokine receptor interaction, and rheumatoid arthritis. The scores of immune cell markers, including neutrophils, monocytes, and macrophages/monocytes were also significantly decreased in non-responders compared with that measured in anti-TNF therapy responders. The KAT2B gene, associated with IL-17 cytokine mediated neutrophil mobilization and activation, was significantly under-expressed in both tissue and peripheral blood mononuclear cells (PBMCs) in anti-TNF therapy-resistant CD patients. The reduced expression of several pro-inflammatory cytokines due to down-regulated IL-17 signaling, is suggestive of the primary non-response to anti-TNF agents in CD patients. Furthermore, the PBMC KAT2B gene signature may be a promising pre-treatment prognostic biomarker for anti-TNF drug response in CD patients.

Artificial intelligence-based measurement outperforms current methods for colorectal polyp size measurement.

OBJECTIVES: An accurate polyp size estimation during colonoscopy is crucial to determine the surveillance interval and predict the risk of malignant progression. However, there is a high degree of subjectivity in estimating polyp size among endoscopists in clinical practice. We aimed to assess the efficacy of a novel method that uses artificial intelligence (AI) to measure the size of colon polyps and compare it with current approaches. METHODS: Using the W-Net model for vessel segmentation and based on retinal image datasets (DRIVE, STARE, CHASE-DB, and HRF) and colonoscopy images, we developed the bifurcation-to-bifurcation (BtoB) distance measuring method and applied it to endoscopic images. Measurements were compared with those obtained by eight endoscopists (four expert and four trainees). Diagnostic ability and reliability were evaluated using Lin's concordance correlation coefficients (CCCs) and Bland-Altman analyses. RESULTS: For both experts and trainees, visually estimated sizes of the same polyp were significantly inconsistent depending on the camera view used (P < 0.001). Bland-Altman analyses showed that there was a trend toward underestimation of the sizes of the polyps in both groups, especially for polyps larger than 10 mm. The new technique was highly accurate and reliable in measuring the size of colon polyp (CCC, 0.961; confidence interval 0.926-0.979), clearly outperforming the visual estimation and open biopsy forceps methods. CONCLUSION: The new AI measurement method improved the accuracy and reliability of polyp size measurements in colonoscopy images. Incorporating AI might be particularly important to improve the efficiency of trainees at estimating polyp size during colonoscopy.

Risk of Metachronous Colorectal Advanced Neoplasia and Cancer in Patients With 3-4 Nonadvanced Adenomas at Index Colonoscopy: A Systematic Review and Meta-Analysis.

INTRODUCTION: This systematic review and meta-analysis evaluated the available evidence on the risk of metachronous advanced neoplasia (AN) and colorectal cancer (CRC) in patients with 3-4 nonadvanced adenomas (NAAs). METHODS: We searched MEDLINE, EMBASE, and Cochrane Library databases up to January 2021 for studies evaluating metachronous AN and CRC risk by comparing 3 groups (1-2 vs 3-4 vs ≥5 NAAs) at index colonoscopy. The estimates for risk of metachronous AN and CRC were evaluated using random-effects models. RESULTS: Fifteen studies (n = 36,375) were included. The risk of metachronous AN was significantly higher in the 3-4 NAAs group than in the 1-2 NAAs group (relative risk [RR] 1.264, 95% confidence interval [CI] 1.053-1.518, P = 0.012; I2 = 0%); there was no difference between the ≥ 5 NAAs and 3-4 NAAs groups (RR 1.962, 95% CI 0.972-3.958, P = 0.060; I2 = 68%). The risks of metachronous CRC between the 1-2 NAAs and 3-4 NAAs groups (RR 2.663, 95% CI 0.391-18.128, P = 0.317; I2 = 0%) or the 3-4 NAAs and ≥ 5 NAAs groups (RR 1.148, 95% CI 0.142-9.290, P = 0.897; I2 = 0%) were not significantly different. DISCUSSION: Although the risk of metachronous AN was greater in the 3-4 NAAs group than in the 1-2 NAAs group, the risk of metachronous AN and CRC between the 3-4 NAAs and ≥ 5 NAAs groups was not different. This suggests that further studies on metachronous AN and CRC risk in the 3-4 NAAs group are warranted to confirm a firm ≥5-year interval surveillance colonoscopy.

Correlation between Surrogate Quality Indicators for Adenoma Detection Rate and Adenoma Miss Rate in Qualified Colonoscopy, CORE Study: KASID Multicenter Study.

Background/Aims: The adenoma detection rate (ADR) does not reflect the complete detection of every adenoma during colonoscopy; thus, many surrogate indicators have been suggested. This study investigated whether the ADR and surrogate quality indicators reflect the adenoma miss rate (AMR) when performing qualified colonoscopy. Methods: We performed a prospective, multicenter, cross-sectional study of asymptomatic examinees aged 50 to 75 years who underwent back-to-back screening colonoscopies by eight endoscopists. The ADR and surrogate quality indicators, including polyp detection rate, total number of adenomas per colonoscopy, additional adenomas found after the first adenoma per colonoscopy (ADR-Plus), and total number of adenomas per positive participant, were calculated for the prediction of AMR. Results: A total of 371 back-to-back colonoscopies were performed. There was a significant difference in ADRs (range, 44% to 75.4%; p=0.024), polyp detection rates (range, 56% to 86.9%; p=0.008) and adenomas per positive participants (range, 1.19 to 2.30; p=0.038), and a tendency of a difference in adenomas per colonoscopy (range, 0.62 to 1.31; p=0.051) and ADR-Plus (range, 0.13 to 0.70; p=0.054) among the endoscopists. The overall AMR was 20.1%, and AMRs were not different (range, 13.9 to 28.6; p>0.05) among the endoscopists. No quality indicators were significantly correlated with AMR. The number of adenomas found during the first colonoscopy was an independent factor for increased AMR (odds ratio, 1.79; p<0.001). Conclusions: The colonoscopy quality indicators were significantly different among high-ADR endoscopists, and none of the quality indicators reflected the AMR of good quality colonoscopy performances. The only factor influencing AMR was the number of adenomas detected during colonoscopy.

Pretreatment with Ranitidine Bismuth Citrate May Improve Success Rates of Helicobacter pylori Eradication: A Prospective, Randomized, Controlled and Open-Label Study.

Effective Helicobacter pylori (H. pylori) eradication is a major public health concern; however, eradication failure rates with the standard triple therapy remain high. We aimed to investigate the effectiveness and tolerability of ranitidine bismuth citrate (RBC) pretreatment before standard triple therapy for H. pylori eradication. A prospective, randomized, controlled, and open-label clinical trial was conducted from June to December 2019. H. pylori eradication rate, safety, and tolerability were compared between the standard treatment group (esomeprazole, amoxicillin, and clarithromycin for 7 days) and RBC pretreatment group (RBC for 2 weeks before standard triple therapy). This trial ended earlier than estimated owing to the N-nitrosodimethylamine concerns with ranitidine. Success rates of H. pylori eradication were 80.9% and 67.3% in the RBC pretreatment (n = 47) and standard treatment (n = 52) (p = 0.126) groups, respectively. Our trial was discontinued earlier than planned; however, a statistical significance would be achieved by expansion of our data (p = 0.031) if patient enrollment numbers reached those initially planned. Adverse event rates were comparable between groups (25.5% in the pretreatment group vs. 28.8% in the standard treatment group), without serious event. Tolerability was excellent in both groups, recorded as 97.9% and 100% in the pretreatment and standard treatment groups, respectively. Compared with the standard triple regimen, RBC pretreatment for 2 weeks may achieve higher H. pylori eradication rates, with excellent safety and tolerability. However, this study necessitates further validation as it was discontinued early owing to the N-nitrosodimethylamine issues of ranitidine.