High risk stigmata and treatment strategy for acute lower gastrointestinal bleeding: a nationwide study in Japan.

BACKGROUND: The rebleeding risks and outcomes of endoscopic treatment for acute lower gastrointestinal bleeding (ALGIB) may differ depending on the bleeding location, type, and etiology of stigmata of recent hemorrhage (SRH) but have yet to be fully investigated. We aimed to identify high risk endoscopic SRH and to propose an optimal endoscopic treatment strategy. METHODS: We retrospectively analyzed 2699 ALGIB patients with SRH at 49 hospitals (CODE BLUE-J Study), of whom 88.6 % received endoscopic treatment. RESULTS: 30-day rebleeding rates of untreated SRH significantly differed among locations (left colon 15.5 % vs. right colon 28.6 %) and etiologies (diverticular bleeding 27.5 % vs. others [e. g. ulcerative lesions or angioectasia] 8.9 %), but not among bleeding types. Endoscopic treatment reduced the overall rebleeding rate (adjusted odds ratio [AOR] 0.69; 95 %CI 0.49-0.98), and the treatment effect was significant in right-colon SRH (AOR 0.46; 95 %CI 0.29-0.72) but not in left-colon SRH. The effect was observed in both active and nonactive types, but was not statistically significant. Moreover, the effect was significant for diverticular bleeding (AOR 0.60; 95 %CI 0.41-0.88) but not for other diseases. When focusing on treatment type, the effectiveness was not significantly different between clipping and other modalities for most SRH, whereas ligation was significantly more effective than clipping in right-colon diverticular bleeding. CONCLUSIONS: A population-level endoscopy dataset allowed us to identify high risk endoscopic SRH and propose a simple endoscopic treatment strategy for ALGIB. Unlike upper gastrointestinal bleeding, the rebleeding risks for ALGIB depend on colonic location, bleeding etiology, and treatment modality.

Potential of Direct Oral Anticoagulant in Bleeding After Gastric Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis.

BACKGROUND AND AIMS: An increasing number of patients are undergoing gastric endoscopic submucosal dissection (ESD) with active prescriptions of direct oral anticoagulants (DOACs). Only a few reports have described the effects of DOAC intake on postoperative bleeding. We aimed to investigate the bleeding risk associated with DOACs after gastric ESD. METHODS: Clinical studies published up to April 2022 showing bleeding rates after gastric ESD in patients taking DOACs were identified using electronic searches. The primary outcome was the rate of bleeding after gastric ESD in patients receiving DOACs compared to those not receiving antithrombotic therapy. In this meta-analysis, odds ratios (ORs) were calculated and pooled using a random effects model. The secondary outcome was the difference in the bleeding rate between patients treated with DOACs and those treated with warfarin and antiplatelet drugs. RESULTS: Seven studies were included in this meta-analysis. The pooled analysis showed that DOACs had a higher bleeding rate than non-thrombotic therapy (17.0% vs. 3.4%; OR 5.72; 95% confidence interval [CI], 4.33-7.54; I2 = 0%). The bleeding risk associated with DOAC administration was similar to that associated with warfarin (17.0% vs. 20.0%; OR 0.83; 95% CI 0.59-1.18; I2 = 0%), whereas it was higher than that associated with antiplatelet administration (16.9% vs. 11.0%; OR 1.63; 95% CI 1.14-2.34; I2 = 8%). CONCLUSIONS: This meta-analysis reveals that the bleeding risk of DOACs is higher than that of non-antithrombotics and antiplatelets, whereas it is comparable to that of warfarin. Gastric ESD in patients on anticoagulants requires careful postoperative management.

Long-term Risks of Recurrence After Hospital Discharge for Acute Lower Gastrointestinal Bleeding: A Large Nationwide Cohort Study.

BACKGROUND & AIMS: Currently, large, nationwide, long-term follow-up data on acute lower gastrointestinal bleeding (ALGIB) are scarce. We investigated long-term risks of recurrence after hospital discharge for ALGIB using a large multicenter dataset. METHODS: We retrospectively analyzed 5048 patients who were urgently hospitalized for ALGIB at 49 hospitals across Japan (CODE BLUE-J study). Risk factors for the long-term recurrence of ALGIB were analyzed by using competing risk analysis, treating death without rebleeding as a competing risk. RESULTS: Rebleeding occurred in 1304 patients (25.8%) during a mean follow-up period of 31 months. The cumulative incidences of rebleeding at 1 and 5 years were 15.1% and 25.1%, respectively. The mortality risk was significantly higher in patients with out-of-hospital rebleeding episodes than in those without (hazard ratio, 1.42). Of the 30 factors, multivariate analysis showed that shock index ≥1 (subdistribution hazard ratio [SHR], 1.25), blood transfusion (SHR, 1.26), in-hospital rebleeding (SHR, 1.26), colonic diverticular bleeding (SHR, 2.38), and thienopyridine use (SHR, 1.24) were significantly associated with increased rebleeding risk. Multivariate analysis of colonic diverticular bleeding patients showed that blood transfusion (SHR, 1.20), in-hospital rebleeding (SHR, 1.30), and thienopyridine use (SHR, 1.32) were significantly associated with increased rebleeding risk, whereas endoscopic hemostasis (SHR, 0.83) significantly decreased the risk. CONCLUSIONS: These large, nationwide follow-up data highlighted the importance of endoscopic diagnosis and treatment during hospitalization and the assessment of the need for ongoing thienopyridine use to reduce the risk of out-of-hospital rebleeding. This information also aids in the identification of patients at high risk of rebleeding.

Timing of colonoscopy in acute lower GI bleeding: a multicenter retrospective cohort study.

BACKGROUND AND AIMS: We aimed to determine the optimal timing of colonoscopy and factors that benefit patients who undergo early colonoscopy for acute lower GI bleeding. METHODS: We identified 10,342 patients with acute hematochezia (CODE BLUE-J study) admitted to 49 hospitals in Japan. Of these, 6270 patients who underwent a colonoscopy within 120 hours were included in this study. The inverse probability of treatment weighting method was used to adjust for baseline characteristics among early (≤24 hours, n = 4133), elective (24-48 hours, n = 1137), and late (48-120 hours, n = 1000) colonoscopy. The average treatment effect was evaluated for outcomes. The primary outcome was 30-day rebleeding rate. RESULTS: The early group had a significantly higher rate of stigmata of recent hemorrhage (SRH) identification and a shorter length of stay than the elective and late groups. However, the 30-day rebleeding rate was significantly higher in the early group than in the elective and late groups. Interventional radiology (IVR) or surgery requirement and 30-day mortality did not significantly differ among groups. The interaction with heterogeneity of effects was observed between early and late colonoscopy and shock index (shock index <1, odds ratio [OR], 2.097; shock index ≥1, OR, 1.095; P for interaction = .038) and performance status (0-2, OR, 2.481; ≥3, OR, .458; P for interaction = .022) for 30-day rebleeding. Early colonoscopy had a significantly lower IVR or surgery requirement in the shock index ≥1 cohort (OR, .267; 95% confidence interval, .099-.721) compared with late colonoscopy. CONCLUSIONS: Early colonoscopy increased the rate of SRH identification and shortened the length of stay but involved an increased risk of rebleeding and did not improve mortality and IVR or surgery requirement. Early colonoscopy particularly benefited patients with a shock index ≥1 or performance status ≥3 at presentation.

Outcomes and recurrent bleeding risks of detachable snare and band ligation for colonic diverticular bleeding: a multicenter retrospective cohort study.

BACKGROUND AND AIMS: Ligation therapy, including endoscopic detachable snare ligation (EDSL) and endoscopic band ligation (EBL), has emerged as an endoscopic treatment for colonic diverticular bleeding (CDB); its comparative effectiveness and risk of recurrent bleeding remain unclear, however. Our goal was to compare the outcomes of EDSL and EBL in treating CDB and identify risk factors for recurrent bleeding after ligation therapy. METHODS: We reviewed data of 518 patients with CDB who underwent EDSL (n = 77) or EBL (n = 441) in a multicenter cohort study named the Colonic Diverticular Bleeding Leaders Update Evidence From Multicenter Japanese Study (CODE BLUE-J Study). Outcomes were compared by using propensity score matching. Logistic and Cox regression analyses were performed for recurrent bleeding risk, and a competing risk analysis was used to treat death without recurrent bleeding as a competing risk. RESULTS: No significant differences were found between the 2 groups in terms of initial hemostasis, 30-day recurrent bleeding, interventional radiology or surgery requirements, 30-day mortality, blood transfusion volume, length of hospital stay, and adverse events. Sigmoid colon involvement was an independent risk factor for 30-day recurrent bleeding (odds ratio, 1.87; 95% confidence interval, 1.02-3.40; P = .042). History of acute lower GI bleeding (ALGIB) was a significant long-term recurrent bleeding risk factor on Cox regression analysis. A performance status score of 3/4 and history of ALGIB were long-term recurrent bleeding factors on competing risk regression analysis. CONCLUSIONS: There were no significant differences in outcomes between EDSL and EBL for CDB. After ligation therapy, careful follow-up is required, especially in the treatment of sigmoid diverticular bleeding during admission. History of ALGIB and performance status at admission are important risk factors for long-term recurrent bleeding after discharge.

Weekend Effect on Clinical Outcomes of Acute Lower Gastrointestinal Bleeding: A Large Multicenter Cohort Study in Japan.

INTRODUCTION: Weekend admissions showed increased mortality in several medical conditions. This study aimed to examine the weekend effect on acute lower gastrointestinal bleeding (ALGIB) and its mortality and other outcomes. METHODS: This retrospective cohort study (CODE BLUE-J Study) was conducted at 49 Japanese hospitals between January 2010 and December 2019. In total, 8,120 outpatients with acute hematochezia were enrolled and divided into weekend admissions and weekday admissions groups. Multiple imputation (MI) was used to handle missing values, followed by propensity score matching (PSM) to compare outcomes. The primary outcome was mortality; the secondary outcomes were rebleeding, length of stay (LOS), blood transfusion, thromboembolism, endoscopic treatment, the need for interventional radiology, and the need for surgery. Colonoscopy and computed tomography (CT) management were also evaluated. RESULTS: Before PSM, there was no significant difference in mortality (1.3% vs. 0.9%, p = 0.133) between weekend and weekday admissions. After PSM with MI, 1,976 cases were matched for each admission. Mortality was not significantly different for weekend admissions compared with weekday admissions (odds ratio [OR] 1.437, 95% confidence interval [CI] 0.785-2.630; p = 0.340). No significant difference was found with other secondary outcomes in weekend admissions except for blood transfusion (OR 1.239, 95% CI 1.084-1.417; p = 0.006). Weekend admission had a negative effect on early colonoscopy (OR 0.536, 95% CI 0.471-0.609; p < 0.001). Meanwhile, urgent CT remained significantly higher in weekend admissions (OR 1.466, 95% CI 1.295-1.660; p < 0.001). CONCLUSION: Weekend admissions decrease early colonoscopy and increase urgent CT but do not affect mortality or other outcomes except transfusion.

Early feeding reduces length of hospital stay in patients with acute lower gastrointestinal bleeding: A large multicentre cohort study.

AIM: No studies have compared the clinical outcomes of early and delayed feeding in patients with acute lower gastrointestinal bleeding (ALGIB). This study aimed to evaluate the benefits and risks of early feeding in a nationwide cohort of patients with ALGIB in whom haemostasis was achieved. METHODS: We reviewed data for 5910 patients with ALGIB in whom haemostasis was achieved and feeding was resumed within 3 days after colonoscopy at 49 hospitals across Japan (CODE BLUE-J Study). Patients were divided into an early feeding group (≤1 day, n = 3324) and a delayed feeding group (2-3 days, n = 2586). Clinical outcomes were compared between the groups by propensity matching analysis of 1508 pairs. RESULTS: There was no significant difference between the early and delayed feeding groups in the rebleeding rate within 7 days after colonoscopy (9.4% vs. 8.0%; p = 0.196) or in the rebleeding rate within 30 days (11.4% vs. 11.5%; p = 0.909). There was also no significant between-group difference in the need for interventional radiology or surgery or in mortality. However, the median length of hospital stay after colonoscopy was significantly shorter in the early feeding group (5 vs. 7 days; p < 0.001). These results were unchanged when subgroups of presumptive and definitive colonic diverticular bleeding were compared. CONCLUSION: The findings of this nationwide study suggest that early feeding after haemostasis can shorten the hospital stay in patients with ALGIB without increasing the risk of rebleeding.

Chronological Changes in Mucosal Deformity by Endoscopic Suturing after Gastric Endoscopic Submucosal Dissection: A Multicenter Retrospective Analysis.

INTRODUCTION: Endoscopic suturing of a mucosal defect is expected to prevent postoperative bleeding after endoscopic submucosal dissection (ESD). Endoscopic suturing causes mucosal deformity, which may interfere with endoscopic surveillance thereafter. We retrospectively investigated long-term chronological changes in mucosal suturing by endoscopic suturing. METHODS: Forty-three patients who underwent endoscopic hand suturing (EHS) after gastric ESD at three institutions were enrolled. First, our hypothesis that the suturing sites healed via inflammation, disappearance of mucosal inversion, and flattening was validated. Subsequently, the duration required to reach each healing step was evaluated. RESULTS: A total of 137 follow-up endoscopies were assessed, in which all cases showed the hypothesized chronological course on the suturing sites. The 95th percentiles of the duration when showing the disappearance of the inflammatory change and the inverted change were 63 days and 15.5 months after the procedure, respectively. DISCUSSION/CONCLUSION: The data show that the mucosal deformity induced by EHS disappeared within 16 months. Endoscopic suturing is thus considered to have a negligible effect on endoscopic surveillance following the procedure.

LONG-HOSP Score: A Novel Predictive Score for Length of Hospital Stay in Acute Lower Gastrointestinal Bleeding - A Multicenter Nationwide Study.

INTRODUCTION: Length of stay (LOS) in hospital affects cost, patient quality of life, and hospital management; however, existing gastrointestinal bleeding models applicable at hospital admission have not focused on LOS. We aimed to construct a predictive model for LOS in acute lower gastrointestinal bleeding (ALGIB). METHODS: We retrospectively analyzed the records of 8,547 patients emergently hospitalized for ALGIB at 49 hospitals (the CODE BLUE-J Study). A predictive model for prolonged hospital stay was developed using the baseline characteristics of 7,107 patients and externally validated in 1,440 patients. Furthermore, a multivariate analysis assessed the impact of additional variables during hospitalization on LOS. RESULTS: Focusing on baseline characteristics, a predictive model for prolonged hospital stay was developed, the LONG-HOSP score, which consisted of low body mass index, laboratory data, old age, nondrinker status, nonsteroidal anti-inflammatory drug use, facility with ≥800 beds, heart rate, oral antithrombotic agent use, symptoms, systolic blood pressure, performance status, and past medical history. The score showed relatively high performance in predicting prolonged hospital stay and high hospitalization costs (area under the curve: 0.70 and 0.73 for derivation, respectively, and 0.66 and 0.71 for external validation, respectively). Next, we focused on in-hospital management. Diagnosis of colitis or colorectal cancer, rebleeding, and the need for blood transfusion, interventional radiology, and surgery prolonged LOS, regardless of the LONG-HOSP score. By contrast, early colonoscopy and endoscopic treatment shortened LOS. CONCLUSIONS: At hospital admission for ALGIB, our novel predictive model stratified patients by their risk of prolonged hospital stay. During hospitalization, early colonoscopy and endoscopic treatment shortened LOS.

Prophylactic use of steroids for a mucosal defect with a circumference of less than three-fourths prevents both symptomatic and asymptomatic stricture after esophageal endoscopic submucosal dissection.

BACKGROUND: Subclinical stricture after esophageal endoscopic submucosal dissection (ESD) makes the detection and re-ESD of metachronous lesions difficult. This study aimed to investigate the effectiveness of prophylactic steroid use after esophageal ESD for mucosal defects with a circumference less than 75% for the prevention of symptomatic and asymptomatic stricture. METHODS: In 80 retrospectively enrolled patients, we collected paired endoscopic images of a mucosal defects immediately after resection and a scar thereafter. After calculating circumference by image analysis software, all patients were classified into three groups in reference to mucosal defect circumference (MDC; ≤ 50%, 50-75%, ≥ 75%). Frequency of steroid use and symptomatic stricture were compared, and in < 75% MDC patients, a degree of asymptomatic stricture with or without steroid was compared by calculating a scar contraction rate (SCR). RESULTS: In the ≤ 50% (43 patients), 50-75% (27 patients) and ≥ 75% (10 patients) MDC groups, steroids were used in 12%, 59% and 100%, respectively, and symptomatic stricture occurred in 0%, 7% and 40%, respectively. In < 75% MDC patients, SCR in the steroid cohort was significantly lower than that in the nonsteroid cohort (42% vs. 65%, p = 0.002). No steroid-related adverse events occurred. CONCLUSION: Steroid use even for mucosal defects with < 75% circumference appears effective for the reduction of the risk on both symptomatic and asymptomatic stricture after esophageal ESD.

Development and validation of a novel model for predicting stigmata of recent hemorrhage in acute lower gastrointestinal bleeding: Multicenter nationwide study.

OBJECTIVES: Stigmata of recent hemorrhage (SRH) directly indicate a need for endoscopic therapy in acute lower gastrointestinal bleeding (LGIB). Colonoscopy would be prioritized for patients with highly suspected SRH, but the predictors of colonic SRH remain unclear. We aimed to construct a predictive model for the efficient detection of SRH using a nationwide cohort. METHODS: We retrospectively analyzed 8360 patients admitted through hospital emergency departments for acute LGIB in the CODE BLUE-J Study (49 hospitals throughout Japan). All patients underwent inpatient colonoscopy. To develop an SRH predictive model, 4863 patients were analyzed. Baseline characteristics, colonoscopic factors (timing, preparation, and devices), and computed tomography (CT) extravasation were extensively assessed. The performance of the model was externally validated in 3497 patients. RESULTS: Colonic SRH was detected in 28% of patients. A novel predictive model for detecting SRH (CS-NEED score: ColonoScopic factors, No abdominal pain, Elevated PT-INR, Extravasation on CT, and DOAC use) showed high performance (area under the receiver operating characteristic curve [AUC] 0.74 for derivation and 0.73 for external validation). This score was also highly predictive of active bleeding (AUC 0.73 for derivation and 0.76 for external validation). Patients with low (0-6), intermediate (7-8), and high (9-12) scores in the external validation cohort had SRH identification rates of 20%, 31%, and 64%, respectively (P < 0.001 for trend). CONCLUSIONS: A novel predictive model for colonic SRH identification (CS-NEED score) can specify colonoscopies likely to achieve endoscopic therapy in acute LGIB. Using the model during initial management would contribute to finding and treating SRH efficiently.

Genetic analysis of Japanese patients with small bowel adenocarcinoma using next-generation sequencing.

BACKGROUND: Small bowel adenocarcinomas (SBAs) are rare and there is little comprehensive data on SBA genomic alterations for Asian patients. This study aimed to profile genomic alterations of SBA in Japanese patients using targeted next-generation sequencing (NGS). METHODS: We examined 22 surgical resections from patients with primary SBA. SBA genomic alterations were analyzed by NGS. Mismatch repair (MMR) status was determined by immunohistochemical analysis. Mucin phenotypes were classified as gastric (G), intestinal (I), gastrointestinal (GI), and null (N) types on MUC2, MUC5AC, MUC6, and CD10 immunostaining. RESULTS: The most common genomic alterations found in SBA tumors were TP53 (n = 16), followed by KRAS (n = 6), APC (n = 5), PIK3CA (n = 4), CTNNB1 (n = 3), KIT (n = 2), BRAF (n = 2), CDKN2A (n = 2), and PTEN (n = 2). Deficient MMR tumors were observed in 6 out of 22 patients. Tumor mucin phenotypes included 2 in G-type, 12 in I-type, 3 in GI-type, and 5 in N-type. APC and CTNNB1 mutations were not found in G-type and GI-type tumors. KRAS mutations were found in all tumor types except for G-type tumors. TP53 mutations were found in all tumor types. Although no single gene mutation was associated with overall survival (OS), we found that KRAS mutations were associated with significant worse OS in patients with proficient MMR tumors. CONCLUSIONS: SBA genomic alterations in Japanese patients do not differ significantly from those reports in Western countries. Tumor localization, mucin phenotype, and MMR status all appear to impact SBA gene mutations.

Treatment strategies for reducing early and late recurrence of colonic diverticular bleeding based on stigmata of recent hemorrhage: a large multicenter study.

BACKGROUND AND AIMS: Treatment strategies for colonic diverticular bleeding (CDB) based on stigmata of recent hemorrhage (SRH) remain unstandardized, and no large studies have evaluated their effectiveness. We sought to identify the best strategy among combinations of SRH identification and endoscopic treatment strategies. METHODS: We retrospectively analyzed 5823 CDB patients who underwent colonoscopy at 49 hospitals throughout Japan (CODE-BLUE J-Study). Three strategies were compared: find SRH (definitive CDB) and treat endoscopically, find SRH (definitive CDB) and treat conservatively, and without finding SRH (presumptive CDB) treat conservatively. In conducting pairwise comparisons of outcomes in these groups, we used propensity score-matching analysis to balance baseline characteristics between the groups being compared. RESULTS: Both early and late recurrent bleeding rates were significantly lower in patients with definitive CDB treated endoscopically than in those with presumptive CDB treated conservatively (<30 days, 19.6% vs 26.0% [P < .001]; <365 days, 33.7% vs 41.6% [P < .001], respectively). In patients with definitive CDB, the early recurrent bleeding rate was significantly lower in those treated endoscopically than in those treated conservatively (17.4% vs 26.7% [P = .038] for a single test of hypothesis; however, correction for multiple testing of data removed this significance). The late recurrent bleeding rate was also lower, but not significantly, in those treated endoscopically (32.0% vs 36.1%, P = .426). Definitive CDB treated endoscopically showed significantly lower early and late recurrent bleeding rates than when treated conservatively in cases of SRH with active bleeding, nonactive bleeding, and in the right-sided colon but not left-sided colon. CONCLUSIONS: Treating definitive CDB endoscopically was most effective in reducing recurrent bleeding over the short and long term, compared with not treating definitive CDB or presumptive CDB. Physicians should endeavor to find and treat SRH for suspected CDB.

Effectiveness and adverse events of endoscopic clipping versus band ligation for colonic diverticular hemorrhage: a large-scale multicenter cohort study.

BACKGROUND : Prior studies have shown the effectiveness of both endoscopic band ligation (EBL) and clipping for colonic diverticular hemorrhage (CDH) but have been small and conducted at single centers. Therefore, we investigated which was the more effective and safe treatment in a multicenter long-term cohort study. METHODS : We reviewed data for 1679 patients with CDH who were treated with EBL (n = 638) or clipping (n = 1041) between January 2010 and December 2019 at 49 hospitals across Japan (CODE BLUE-J study). Logistic regression analysis was used to compare outcomes between the two treatments. RESULTS : In multivariate analysis, EBL was independently associated with reduced risk of early rebleeding (adjusted odds ratio [OR] 0.46; P < 0.001) and late rebleeding (adjusted OR 0.62; P < 0.001) compared with clipping. These significantly lower rebleeding rates with EBL were evident regardless of active bleeding or early colonoscopy. No significant differences were found between the treatments in the rates of initial hemostasis or mortality. Compared with clipping, EBL independently reduced the risk of needing interventional radiology (adjusted OR 0.37; P = 0.006) and prolonged length of hospital stay (adjusted OR 0.35; P < 0.001), but not need for surgery. Diverticulitis developed in one patient (0.16 %) following EBL and two patients (0.19 %) following clipping. Perforation occurred in two patients (0.31 %) following EBL and none following clipping. CONCLUSIONS : Analysis of our large endoscopy dataset suggests that EBL is an effective and safe endoscopic therapy for CDH, offering the advantages of lower early and late rebleeding rates, reduced need for interventional radiology, and shorter length of hospital stay.

Prophylactic clip closure for mucosal defects is associated with reduced adverse events after colorectal endoscopic submucosal dissection: a propensity-score matching analysis.

BACKGROUND: It is unclear whether prophylactic endoscopic closure after colorectal endoscopic submucosal dissection (ESD) reduces the risk of postoperative adverse events due to variability in lesion characteristics. Therefore, we conducted a retrospective study using propensity score matching to evaluate the efficacy of prophylactic clip closure in preventing postoperative adverse events after colorectal ESD. METHODS: This single-center retrospective cohort study included 219 colorectal neoplasms which were removed by ESD. The patients were allocated into the closure and non-closure groups, which were compared before and after propensity-score matching. Post-ESD adverse events including major and minor bleeding and delayed perforation were compared between the two groups. RESULTS: In this present study, 97 and 122 lesions were allocated to the closure and non-closure groups, respectively, and propensity score matching created 61 matched pairs. The rate of adverse events was significantly lower in the closure group than in the non-closure group (8% vs. 28%, P = 0.008). Delayed perforation occurred in two patients in the non-closure group, whereas no patient in the closure group developed delayed perforation. In contrast, there were no significant differences in other postoperative events including the rate of abdominal pain; fever, white blood cell count, and C-reactive protein; and appetite loss between the two groups. CONCLUSIONS: Propensity score matching analysis demonstrated that prophylactic closure was associated with a significantly reduced rate of adverse events after colorectal ESD. When technically feasible, mucosal defect closure after colorectal ESD may result in a favorable postoperative course.

Convolutional neural network-based system for endocytoscopic diagnosis of early gastric cancer.

BACKGROUND: Endocytoscopy (ECS) aids early gastric cancer (EGC) diagnosis by visualization of cells. However, it is difficult for non-experts to accurately diagnose EGC using ECS. In this study, we developed and evaluated a convolutional neural network (CNN)-based system for ECS-aided EGC diagnosis. METHODS: We constructed a CNN based on a residual neural network with a training dataset comprising 906 images from 61 EGC cases and 717 images from 65 noncancerous gastric mucosa (NGM) cases. To evaluate diagnostic ability, we used an independent test dataset comprising 313 images from 39 EGC cases and 235 images from 33 NGM cases. The test dataset was further evaluated by three endoscopists, and their findings were compared with CNN-based results. RESULTS: The trained CNN required 7.0 s to analyze the test dataset. The area under the curve of the total ECS images was 0.93. The CNN produced 18 false positives from 7 NGM lesions and 74 false negatives from 28 EGC lesions. In the per-image analysis, the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 83.2%, 76.4%, 92.3%, 93.0%, and 74.6%, respectively, with the CNN and 76.8%, 73.4%, 81.3%, 83.9%, and 69.6%, respectively, for the endoscopist-derived values. The CNN-based findings had significantly higher specificity than the findings determined by all endoscopists. In the per-lesion analysis, the accuracy, sensitivity, specificity, PPV, and NPV of the CNN-based findings were 86.1%, 82.1%, 90.9%, 91.4%, and 81.1%, respectively, and those of the results calculated by the endoscopists were 82.4%, 79.5%, 85.9%, 86.9%, and 78.0%, respectively. CONCLUSIONS: Compared with three endoscopists, our CNN for ECS demonstrated higher specificity for EGC diagnosis. Using the CNN in ECS-based EGC diagnosis may improve the diagnostic performance of endoscopists.

Circularity Is a Potential Noninvasive Diagnostic Indicator to Differentiate Gastric Submucosal Tumors.

BACKGROUND AND AIMS: Noninvasive, imaging diagnosis of gastrointestinal mesenchymal tumors (GIMTs) is still difficult. This study aimed to develop a novel diagnostic method of GIMTs via endoscopic ultrasonography (EUS) using circularity. METHODS: In a derivation series, we retrospectively collected 50 GIMTs 2-5 cm in diameter of two institutions. After selecting one EUS still image showing the maximal area per lesion, two endoscopists who were blind to the histological diagnosis assessed circularity, a surrogate indicator of roundness (range, 0-1; 1 = a true circle), with an image-analyzing software. Median circularity of three types of GIMT was compared, and the cutoff value to differentiate a group from other groups was presented by drawing a receiver operating characteristic curve. Subsequently, we assessed the diagnostic ability of circularity in 91 GIMTs which were retrospectively collected from the other two institutions by using the optimal cutoff value presented in the derivation series. RESULTS: The circularity in leiomyomas indicated 0.70 and was significantly lower than that of gastrointestinal stromal tumors (0.89), schwannomas (0.90), and their combined group. When leiomyomas were diagnosed as the circularity of <0.8305, which was presented as the optimal cutoff value, the diagnostic accuracy, sensitivity, and specificity in the validation series were 73.6%, 80.0%, and 72.4%, respectively. CONCLUSION: The data demonstrated that leiomyomas significantly exhibited more distortion than other GIMTs. That implies that the difference in shape, which is objectively determined as circularity, is useful to noninvasively discriminate leiomyomas from other GIMTs.

Bilateral Risk Assessments of Surgery and Nonsurgery Contribute to Providing Optimal Management in Early Gastric Cancers after Noncurative Endoscopic Submucosal Dissection: A Multicenter Retrospective Study of 485 Patients.

BACKGROUND AND AIMS: Surgery is recommended in early gastric cancer (EGC) after noncurative endoscopic submucosal dissection (ESD), although observation can be an alternative. We aimed to develop a tailor-made treatment strategy for noncurative EGCs by comparing the lymph node metastasis risk (LNMR) and the surgical risk. METHODS: We retrospectively identified 485 patients with differentiated-type, noncurative EGCs removed by ESD and classified them into two groups: a surgery-preferable group and an observation-preferable group, according to the clinical courses. Subsequently, LNMR and surgery-related death risk were assessed using a published scoring system and a risk calculator for gastrectomy, respectively. Finally, we investigated the optimal cutoff value of the risk difference (LNMR minus surgery-related death risk) to efficiently allocate these cases into either of two groups, surgery-preferable or observation-preferable. RESULTS: In 485 patients (surgery in 322, observation in 163), 57 and 428 patients were classified into the surgery-preferable group and the observation-preferable group, respectively. The optimal cutoff value of the risk difference (LNMR minus surgery-related death risk) to allocate the cases to the two preferable groups was 7.85 with the highest area under the curve (0.689). When cases with >7.85 LNMR over the surgery-related death risk were allocated into the surgery-preferable group and vice versa, the discriminability was 73.2%, which was sufficiently higher than that in the clinical decision (44.5%). CONCLUSION: Personalized comparison of LNMR and surgery-related death risk is helpful to provide a favorable treatment option for each patient with EGCs after noncurative ESD.

Identifying Bleeding Etiologies by Endoscopy Affected Outcomes in 10,342 Cases With Hematochezia: CODE BLUE-J Study.

INTRODUCTION: The bleeding source of hematochezia is unknown without performing colonoscopy. We sought to identify whether colonoscopy is a risk-stratifying tool to identify etiology and predict outcomes and whether presenting symptoms can differentiate the etiologies in patients with hematochezia. METHODS: This multicenter retrospective cohort study conducted at 49 hospitals across Japan analyzed 10,342 patients admitted for outpatient-onset acute hematochezia. RESULTS: Patients were mostly elderly population, and 29.5% had hemodynamic instability. Computed tomography was performed in 69.1% and colonoscopy in 87.7%. Diagnostic yield of colonoscopy reached 94.9%, most frequently diverticular bleeding. Thirty-day rebleeding rates were significantly higher with diverticulosis and small bowel bleeding than with other etiologies. In-hospital mortality was significantly higher with angioectasia, malignancy, rectal ulcer, and upper gastrointestinal bleeding. Colonoscopic treatment rates were significantly higher with diverticulosis, radiation colitis, angioectasia, rectal ulcer, and postendoscopy bleeding. More interventional radiology procedures were needed for diverticulosis and small bowel bleeding. Etiologies with favorable outcomes and low procedure rates were ischemic colitis and infectious colitis. Higher rates of painless hematochezia at presentation were significantly associated with multiple diseases, such as rectal ulcer, hemorrhoids, angioectasia, radiation colitis, and diverticulosis. The same was true in cases of hematochezia with diarrhea, fever, and hemodynamic instability. DISCUSSION: This nationwide data set of acute hematochezia highlights the importance of colonoscopy in accurately detecting bleeding etiologies that stratify patients at high or low risk of adverse outcomes and those who will likely require more procedures. Predicting different bleeding etiologies based on initial presentation would be challenging.

Three-dimensional visualization improves the endoscopic diagnosis of superficial gastric neoplasia.

BACKGROUND: Three-dimensional (3D) technology has been used in many fields, including flexible endoscopy. We evaluated the usefulness of 3D visualization for endoscopically diagnosing superficial gastric neoplasia. METHODS: Twelve participants (4 novices, 4 trainees and 4 experts) evaluated two-dimensional (2D) and 3D endoscopic still images of 28 gastric neoplasias, obtained before ESD with white-light imaging (WLI) and narrow-band imaging (NBI). Assessments of the delineation accuracy of tumor extent and tumor morphology under 2D and 3D visualization were based on the histopathological diagnosis of ESD specimens. Participants answered visual analog scale (VAS) questionnaires (0-10, worst to best) concerning the (a) ease of recognition of lesion morphology, (b) lesion extent and (c) comprehensive endoscopic cognition under 2D and 3D visualization. The endpoints were the accuracy of tumor extent and morphology type and the degree of confidence in assessing (a)-(c). RESULTS: The delineation accuracy of lesion extent [mean (95% confidence interval)] with WLI under 3D visualization [60.2% (56.1-64.3%)] was significantly higher than that under 2D visualization [52.3% (48.2-56.4%)] (P < 0.001). The accuracy with NBI under 3D visualization [70.3% (66.8-73.7%)] was also significantly higher than that under 2D visualization [64.2% (60.7-67.4%)] (P < 0.001). The accuracy of the morphology type with NBI under 3D visualization was significantly higher than that under 2D visualization (P = 0.004). The VAS for all aspects of endoscopic recognition under 3D visualization was significantly better than that under 2D visualization (P < 0.01). CONCLUSIONS: Three-dimensional visualization can enhance the diagnostic quality for superficial gastric tumors.