Search

The role of a covered vs. an uncovered self-expandable metal stent (SEMS) for malignant distal biliary obstruction (MDBO) is not clear. This meta-analysis compared the efficacy of covered vs. uncovered SEMS for patients with MDBO after endoscopic insertion.A systematic meta-analysis of all relevant articles listed in PubMed, the Cochrane Library, and Google Scholar databases was performed. Fixed effects or random effects models were used to investigate pooled effects with 95% confidence intervals (CIs).The meta-analysis included 2358 patients from 12 eligible studies. Time to recurrent biliary obstruction (RBO) was significantly longer for covered SEMS (mean difference, 45.51 days; 95% CI 11.79-79.24). Although there was no significant difference in the RBO rate, subgroup analysis in pancreatic cancer occupying more than 90% (PC) revealed that the RBO rates were significantly lower for covered SEMS (odds ratio [OR] 0.43, 95% CI 0.25-0.74). Stent migration, sludge formation, and overgrowth were significantly more common with a covered SEMS (OR 7.92, 95% CI 4.01-15.64; OR 3.25, 95% CI 1.89-5.59; OR 2.03, 95% CI 1.20-3.43, respectively). The rate of ingrowth was significantly lower for covered SEMS. There was no significant difference in total procedure-related adverse events between the two types of SEMS.A covered SEMS is superior to an uncovered SEMS with respect to prevention of RBO in patients with MDBO, particularly those caused by PC.

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

We propose a depth estimation method from a single-shot monocular endoscopic image using Lambertian surface translation by domain adaptation and depth estimation using multi-scale edge loss. We employ a two-step estimation process including Lambertian surface translation from unpaired data and depth estimation. The texture and specular reflection on the surface of an organ reduce the accuracy of depth estimations. We apply Lambertian surface translation to an endoscopic image to remove these texture and reflections. Then, we estimate the depth by using a fully convolutional network (FCN). During the training of the FCN, improvement of the object edge similarity between an estimated image and a ground truth depth image is important for getting better results. We introduced a muti-scale edge loss function to improve the accuracy of depth estimation. We quantitatively evaluated the proposed method using real colonoscopic images. The estimated depth values were proportional to the real depth values. Furthermore, we applied the estimated depth images to automated anatomical location identification of colonoscopic images using a convolutional neural network. The identification accuracy of the network improved from 69.2% to 74.1% by using the estimated depth images., Comment: Accepted paper as an oral presentation at Joint MICCAI workshop 2021, AE-CAI/CARE/OR2.0

Objectives There are patients who do not undergo colonoscopy even if the fecal immunochemistry test (FIT) results are positive and even with repeated positive test results the following year. We aimed to investigate colorectal cancer (CRC) risk in examinees with positive FIT results in our annual screening program. Methods We analyzed patients who underwent initial colonoscopy from April 2010 to March 2017 because of positive FIT results using an endoscopy database in our hospital. We investigated the difference in the risk of advanced colorectal neoplasia as a surrogate marker of CRC between those who had an initial positive test and those who had repeated positive tests. Results A total of 748 patients were included in this analysis. The advanced neoplasia detection rates were 7.6% (50/656) and 18.5% (17/92) for the initial and repeated positive test groups, respectively. Subgroup analysis of those with repeated positive tests revealed that the detection rates in examinees with positive tests 1-2 and >2 years ago were 16.7% (6/36) and 19.6% (11/56), respectively. The odds ratios for advanced neoplasia detection in patients with positive tests 1-2 and >2 years ago compared with those in the initial positive test group were 2.72 (95% confidence interval [CI], 1.04-7.10) and 3.09 (95% CI, 1.47-6.48), respectively. Conclusions The risk of CRC appears more than doubled in patients with a repeated positive FIT result. Prompt colonoscopy is recommended for FIT-positive cases.

Background Ischemic colitis is an adverse event which may occur during bowel preparation for colonoscopy. This study aims to clarify both the incidence and the risk factors of this complication. Methods This was a single-center, retrospective, observational study. All outpatients who were prescribed standardized preparation drugs for colonoscopy at the Kyoto Second Red Cross Hospital between November 2011 and March 2020 were included in the study. A split bowel preparation was carried out as follows; magnesium citrate with or without sodium picosulfate hydrate was/were used as a preparation drug on the day before the colonoscopy, and polyethylene glycol electrolyte solution or sodium phosphate was used on the morning of the endoscopic procedure. Patients were extracted from the electronic medical records and matched with the endoscopy database by examination date and hospital identification number. Following the endoscopic findings, both the incidence and risk factors for ischemic colitis arising after bowel preparation were examined. Results Among the 14,924 patients analyzed, ischemic colitis was observed in 14 patients (0.09%). Multivariate analysis revealed that old age (≥ 75 years old) and strong preparation (magnesium citrate with sodium picosulfate and polyethylene glycol electrolyte solution) for constipated patients were independent risk factors for ischemic colitis (odds ratio: 3.64 (95% confidence interval (CI): 1.36 - 9.77) and 4.27 (95% CI: 1.45 - 12.53), respectively). Conclusions The age 75 years and above and strong preparation for patients with constipation were independent risk factors for ischemic colitis prior to colonoscopy. Careful attention should be paid to bowel preparation before colonoscopy for patients aged ≥ 75 years and for those with constipation.

Objectives The Japan Endoscopy Database Project was initiated to develop the world's largest endoscopy data repository. This study describes the first phase of the colonoscopy project in Japan. Methods Data were aggregated offline by integrating information from the endoscopy database software from January 2015 through March 2017. The study population included all patients who underwent colonoscopy at eight centers. Results A total of 31,395 patients who underwent 38,497 colonoscopy procedures were registered. The majority of procedures were performed for screening (n = 14,156), followed by fecal immunochemical test positivity (n = 3960), abdominal symptoms (n = 3864), post-colorectal surgery surveillance (n = 3431), post-endoscopic treatment surveillance (n = 3757), thorough pre-treatment examination (n = 2822), and therapeutic purposes (n = 6507). In the screening group, advanced cancers, early cancers, and adenomas were diagnosed endoscopically in 2.1%, 1.3%, and 28.7% of cases, respectively, while in the fecal immunochemical test-positive group, they were diagnosed in 2.5%, 1.9%, and 41.6% of cases, respectively. The incidence of complications was 0.177% and 0.152% in the screening and fecal immunochemical test-positive groups, respectively. The therapeutic procedures included 1446 cold forceps polypectomy procedures, 4770 cold snare polypectomy procedures, 368 hot biopsies, 2998 hot snare polypectomy procedures, 9775 endoscopic or piecemeal endoscopic mucosal resections, and 1660 endoscopic submucosal dissections. A total of 173 procedure-related complications (0.82%) occurred in 21,017 therapeutic procedures performed in 15,744 patients. Conclusions The first phase of the Japan Endoscopy Database Project established the proportions of the diagnostic and therapeutic colonoscopy procedures, and complication rates in real-world settings.

Background and Aim As the significance of the quantitative fecal immunochemical test (FIT) in patients who previously underwent a colonoscopy is unknown, this study aimed at investigating the association between fecal hemoglobin concentration and the risk of colorectal cancer (CRC). Methods and Results We retrospectively analyzed FIT‐positive patients who underwent a colonoscopy through our opportunistic annual screening program from April 2010 to March 2017 at the Kyoto Second Red Cross Hospital. We stratified them into no colonoscopy and past colonoscopy (>5 years or ≤5 years) groups based on whether they had a history of undergoing a colonoscopy and analyzed the correlation between fecal hemoglobin concentration and advanced neoplasia or invasive cancer detection in each group. We analyzed 1248 patients with positive FIT results. There were 748 (59.9%), 198 (15.9%), and 302 (24.2%) patients in the no colonoscopy, past colonoscopy (>5 years), and past colonoscopy (≤5 years) groups, respectively. In the no colonoscopy group, the advanced neoplasia detection rate significantly increased with the fecal hemoglobin concentration (P 5 years and ≤5 years) group (P = 0.982). No invasive cancer was detected in the past colonoscopy (≤5 years) group. Conclusion The risk of CRC might be low even if fecal hemoglobin concentration was high, especially in those who underwent colonoscopy within 5 years., We retrospectively analyzed fecal immunochemistrytest positive patients who underwent a colonoscopy. We stratified them into the no colonoscopy and past colonoscopy (>5 years or ≤5 years) groups based on whether they had a history of undergoing a colonoscopy and analyzed the correlation between fecal hemoglobin concentration and advanced neoplasia detection in each group. In the no colonoscopy group, the advanced neoplasia detection rate significantly increased with the fecal hemoglobin concentration. However, no significant trend was observed in the past colonoscopy (both ≥5 years and ≤5 years) group. Especially in those who underwent colonoscopy within 5 years, risk of colorectal cancer might be low even if fecal hemoglobin concentration was high.

Background. Retention of surgical sponges in patients is a relatively frequent medical malpractice. To prevent it, the surgical sites are scanned using X-ray. However, using radiography in the operation room induces X-ray exposure for both patients and staff. To prevent such issues, a novel sponge counting system was developed. Each surgical sponge used in common hospitals is composed of single radiopaque fibers. Methods. The proposed system scans surgical sponges to estimate their fiber length (EFL) and returns the number of it. In this study, an optimal image acquisition protocol was determined that allows an accurate count of sponges. X-ray doses and multi-angle image procedures were tested. Results. Measurement trials were performed and compared for both dry and blood-soaked sponges. As a result, the X-ray dose of 50 kV and 600 μA and the acquisition of 180 images per sample yielded an accurate EFL. The 180-image protocol achieved good performance in this study and allowed counting of one package of 10 sponges in 226 seconds. For these settings, a significant correlation was found between the actual number of sponges and the estimated fiber lengths. Additionally, the performance of the system was similar for either dry or blood-soaked items. Conclusion. The proposed system could accurately count surgical sponges and is a promising option in preventing the accidental retention of surgical sponges.

BACKGROUND Different types of periampullary diverticulum (PAD) may differentially affect the success of endoscopic retrograde cholangiopancreatography (ERCP) cannulation, but the clinical significance of the two current PAD classifications for cannulation is limited. AIM To verify the clinical value of our newly proposed PAD classification. METHODS A new PAD classification (Li-Tanaka classification) was proposed at our center. All PAD patients with native papillae who underwent ERCP from January 2012 to December 2017 were classified according to three classification systems, and the effects of various types of PAD on ERCP cannulation were compared. RESULTS A total of 3564 patients with native papillae were enrolled, including 967 (27.13%) PAD patients and 2597 (72.87%) non-PAD patients. In the Li-Tanaka classification, type I PAD patients exhibited the highest difficult cannulation rate (23.1%, P = 0.01), and type II and IV patients had the highest cannulation success rates (99.4% in type II and 99.3% in type IV, P < 0.001). In a multivariable-adjusted logistic model, the overall successful cannulation rate in PAD patients was higher than that in non-PAD patients [odds ratio (OR) = 1.87, 95% confidence interval (CI): 1.04-3037, P = 0.037]. In addition, compared to the non-PAD group, the difficulty of cannulation in the type I PAD group according to the Li-Tanaka classification was greater (OR = 2.04, 95%CI: 1.13-3.68, P = 0.004), and the successful cannulation rate was lower (OR = 0.27, 95%CI: 0.11-0.66, P < 0.001), while it was higher in the type II PAD group (OR = 4.44, 95%CI: 1.61-12.29, P < 0.01). CONCLUSION Among the three PAD classifications, the Li-Tanaka classification has an obvious clinical advantage for ERCP cannulation, and it is helpful for evaluating potentially difficult and successful cannulation cases among different types of PAD patients.

The aim of this study was to identify the incidence of and risk factors for post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) after emergency endoscopic retrograde cholangiopancreatography (ERCP).We performed a prospective multicenter observational study of 3914 patients who underwent ERCP. We compared the incidence of PEP after emergency and elective ERCP.A total of 3410 patients were enrolled in this study. Post-ERCP pancreatitis occurred in 44 of 800 patients (5.5%) and in 190 of 2418 patients (7.9%) in the emergency and elective groups, respectively. No significant difference was noted between the groups (odds ratio [OR], 0.73; 95% confidence interval [CI], 0.52-1.03; P = 0.07). Multivariate analysis showed that the following factors increased the risk for PEP after emergency ERCP: contrast medium injection into the pancreatic duct (OR, 2.56; 95% CI, 1.30-5.03; P = 0.005),4 cannulation attempts (OR, 5.72; 95% CI, 2.61-12.50; P0.001), and endoscopic papillary balloon dilatation (OR, 9.24; 95% CI, 2.13-40.10; P0.001).No significant difference was noted in the incidence of PEP in patients after emergency and elective ERCP. We may prevent PEP even after emergency ERCP by avoiding contrast injection into the pancreatic duct, multiple cannulation attempts, and endoscopic papillary balloon dilatation.

This paper proposes a realistic image generation method for visualization in endoscopic simulation systems. Endoscopic diagnosis and treatment are performed in many hospitals. To reduce complications related to endoscope insertions, endoscopic simulation systems are used for training or rehearsal of endoscope insertions. However, current simulation systems generate non-realistic virtual endoscopic images. To improve the value of the simulation systems, improvement of reality of their generated images is necessary. We propose a realistic image generation method for endoscopic simulation systems. Virtual endoscopic images are generated by using a volume rendering method from a CT volume of a patient. We improve the reality of the virtual endoscopic images using a virtual-to-real image-domain translation technique. The image-domain translator is implemented as a fully convolutional network (FCN). We train the FCN by minimizing a cycle consistency loss function. The FCN is trained using unpaired virtual and real endoscopic images. To obtain high quality image-domain translation results, we perform an image cleansing to the real endoscopic image set. We tested to use the shallow U-Net, U-Net, deep U-Net, and U-Net having residual units as the image-domain translator. The deep U-Net and U-Net having residual units generated quite realistic images., Accepted paper as an oral presentation at the Joint MICCAI workshop MIAR | AE-CAI | CARE 2019

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

Endoscopic sphincterotomy is the established treatment for common bile duct stones. Balloon dilation offers an alternative. Prolonged dilation (300 s) with a 10 mm diameter balloon decreases the occurrence of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). We aimed to determine the optimal duration of dilation for combined endoscopic sphincterotomy and balloon dilation for the removal of common bile duct stones.We did a multicentre, single-blinded, randomised controlled trial at 15 tertiary surgical centres in China. Eligible patients (≥18 years) with native papilla and common bile duct stones (≤1·5 cm in size and2 cm in diameter) undergoing ERCP were randomly assigned (1:1:1:1:1) to receive balloon dilation for 0, 30, 60, 180, or 300 s after deep bile duct cannulation. Randomisation was done by an independent statistician using a computer-generated randomisation list with a block size of ten, stratified by centre. Patients and outcome assessors, but not endoscopists and investigators, were masked to treatment allocation. Balloon dilation was done with controlled radial expansion balloons according to common bile duct stone size. Stones were removed using stone retrieval balloons or baskets. The primary endpoint was overall frequency of post-ERCP pancreatitis. The primary efficacy analysis and safety analyses were done in the modified intention-to-treat population, which included all randomly assigned patients with successful cannulation, but excluded those who withdrew consent after randomisation. This study was registered with ClinicalTrials.gov, number NCT02510495, and is complete.Between July 29, 2015, and Dec 1, 2017, 3721 consecutive patients with common bile duct stones were recruited, 1718 of whom were excluded. The remaining 2003 patients underwent a small (3-5 mm) endoscopic sphincterotomy. 83 patients withdrew consent after the ERCP procedure, thus 1920 patients were included in the modified intention-to-treat analysis (0 s [n=371], 30 s [n=384], 60 s [n=388], 180 s [n=390], and 300 s [n=387]). Overall, post-ERCP pancreatitis occurred in 199 (10%) of 1920 patients (44 [12%] patients in the 0 s group, 28 [7%] in the 30 s group, 32 [8%] in the 60 s group, 36 [9%] in the 180 s group, and 59 [15%] in the 300 s group). Prolonged dilation (300 s) significantly increased the occurrence of post-ERCP pancreatitis compared with shorter balloon dilation (p=0·002). The frequency of post-ERCP pancreatitis was significantly lower in the 30, 60, and 180 s groups than in the 300 s group (relative risk [RR] 0·48, 95% CI 0·31-0·73; p=0·0005 vs the 30 s group; 0·54, 0·36-0·81; p=0·003 vs the 60 s group; 0·61, 0·41-0·89; p=0·01 vs the 180 s group). The frequency of post-ERCP pancreatitis was significantly higher in the 0 s group than the 30 s group (RR 1·62, 1·04-2·56; p=0·03). No difference in stone extraction (all ≥90%) was observed between groups. Following ERCP, 90 (5%) of 1920 patients had acute cholangitis, 14 (1%) had acute cholecystitis, and five (1%) had gastrointestinal bleeding, with no significant differences between groups. One (1%) patient had Stapfer II perforation, which resolved spontaneously with conservative treatment.A balloon dilation time of 30 s for combined endoscopic sphincterotomy and balloon dilation reduced the frequency of post-ERCP pancreatitis and was determined to be the optimum dilation time for the removal of common bile duct stones.National Natural Science Foundation of China, Gansu Competitive Foundation Projects for Technology Development and Innovation.

Background and Aims This study aimed to evaluate the efficacy of perioperative antibiotics against post–endoscopic submucosal dissection (ESD) coagulation syndrome (PECS) in patients undergoing colorectal ESD. Methods A prospective, multicenter, randomized controlled, parallel, superiority trial was conducted at 21 Japanese tertiary institutions. Patients with superficial colorectal lesions ≥20 mm and those undergoing ESD management for a single lesion were eligible. Patients with perforation during and after ESD were withdrawn. Before the ESD procedure, participants were randomly assigned (1:1) to either undergo conventional treatment (nonantibiotic group) or investigational treatment (antibiotic group). In the antibiotic group, 3 g of ampicillin-sulbactam was administered just before, 8 hours after, and the morning after ESD. The primary endpoint was the incidence of PECS. The onset of PECS was defined as localized abdominal pain (both spontaneous pain and tenderness) and fever (≥37.6°C) or inflammatory response (leukocytosis [≥10,000 cells/μL] or elevated C-reactive protein level [≥.5 mg/dL]). Results From February 5, 2019 to September 7, 2020, 432 patients were enrolled and assigned to the antibiotic group (n = 216) or nonantibiotic group (n = 216). After withdrawal of 52 patients, 192 in the antibiotic group and 188 in the nonantibiotic group were analyzed. PECS occurred in 9 of 192 patients (4.7%) in the antibiotic group and 14 of 188 patients (7.5%) in the nonantibiotic group, with an odds ratio of .61 (95% confidence interval, .23-1.56; P = .29). Conclusions Perioperative use of antibiotics was not effective in reducing the incidence of PECS in patients undergoing colorectal ESD. (Clinical trial registration number: UMIN000035178.)

Ulcerative colitis (UC) classification, which is an important task for endoscopic diagnosis, involves two main difficulties. First, endoscopic images with the annotation about UC (positive or negative) are usually limited. Second, they show a large variability in their appearance due to the location in the colon. Especially, the second difficulty prevents us from using existing semi-supervised learning techniques, which are the common remedy for the first difficulty. In this paper, we propose a practical semi-supervised learning method for UC classification by newly exploiting two additional features, the location in a colon (e.g., left colon) and image capturing order, both of which are often attached to individual images in endoscopic image sequences. The proposed method can extract the essential information of UC classification efficiently by a disentanglement process with those features. Experimental results demonstrate that the proposed method outperforms several existing semi-supervised learning methods in the classification task, even with a small number of annotated images.

Anoikis is a form of apoptosis, which inhibits metastatic cascade and deprives cancer cells with invasive capacity. Epidermal growth factor-like domain-containing protein 7 (EGFL7) is overexpressed in colorectal cancer (CRC) and is a potential biomarker for malignancy. The present study aimed was to investigate the effect and underlying mechanism of EGFL7 on CRC cell function. EGFL7 expression in mutable human CRC cell lines and normal intestinal epithelial cell line HIEC were measured by qRT-PCR. To investigate the biological functions of EGFL7, loss-of-function experiments were performed by transfecting EGFL7 siRNA into SW620 and LoVo cells. Western blot analysis, MTT, invasion and anoikis assay were used to explore the underlying mechanism of EGFL7. EGFL7 was upregulated in several CRC cell lines as compared with normal intestinal epithelial cell line HIEC. Transfection of EGFL7 siRNA significantly decreased cell proliferation and invasion capacity of SW620 and LoVo cells. Additionally, EGFL7 inhibition markedly elevated anoikis through modulating anoikis marker proteins as reflected by increasing of cleaved-caspase-3 and cleaved-PAPR expression. Moreover, downregulation of EGFL7 inhibited PI3K and P-AKT expression. Furthermore, re-expression of PI3K remarkably reversed the effects of EGFL7 on SW620 cells. Overall, our findings suggested that EGFL7 acts as an oncogene, regulated CRC invasion and anoikis through PI3K/AKT signaling, which provided a theoretical basis for EGFL7 as a potential therapeutic target of CRC treatment.

When using deep neural networks in medical image classification tasks, it is mandatory to prepare a large-scale labeled image set, and this often requires significant effort by medical experts. One strategy to reduce the labeling cost is group-based labeling, where image samples are clustered and then a label is attached to each cluster. The efficiency of this strategy depends on the purity of the clusters. Constrained clustering is an effective way to improve the purity of the clusters if we can give appropriate must-links and cannot-links as constraints. However, for medical image clustering, the conventional constrained clustering methods encounter two issues. The first issue is that constraints are not always appropriate due to the gap between semantic and visual similarities. The second issue is that attaching constraints requires extra effort from medical experts. To deal with the first issue, we propose a novel soft-constrained clustering method, which has the ability to ignore inappropriate constraints. To deal with the second issue, we propose a self-constrained clustering method that utilizes prior knowledge about the target images to set the constraints automatically. Experiments with the endoscopic image datasets demonstrated that the proposed methods give clustering results with higher purity.

Hypoxia leads to cancer progression and promotes the metastatic potential of cancer cells. Thereby, the aim of the present study was to investigate the detailed effects of gene associated with retinoid-interferon-induced mortality-19 (GRIM-19) in colorectal cancer (CRC) cell lines under hypoxia conditions and explore the potential molecular mechanisms. Here, we observed that GRIM-19 expression was downregulated in several CRC cell lines as well as in HCT116 and Caco-2 cells under a hypoxic microenvironment. Additionally, the introduction of GRIM-19 obviously suppressed cell invasive ability and epithelial-mesenchymal transition (EMT) through modulating EMT markers as reflected by the upregulation of E-cadherin along with the downregulation of vimentin and N-cadherin under hypoxic conditions. Moreover, the addition of GRIM-19 repressed hypoxia-induced autophagy through modulating autophagy associated proteins as reflected by the downregulation of LC3-II/LC3-I ratio and Beclin-1 expression, as well as the increased of p62 expression. Interestingly, overexpression of GRIM-19 markedly ameliorated the accumulation of HIF-1α triggered by hypoxia accompanied by an inhibition of vascular endothelial growth factor (VEGF) production and phospho-signal transducer and activator of transcription 3 (p-STAT3) expression. Further data demonstrated that GRIM-19 have a negative feedback effect on the expression of HIF-1α. Mechanistically, re-expression of HIF-1α completely reversed the inhibitory effects of GRIM-19 on hypoxia-induced invasion and EMT. Taken all data together, our findings established that GRIM-19 suppresses hypoxia-triggered invasion and EMT by inhibiting hypoxia-induced autophagy through inactivation HIF-1α/STAT3 signaling pathway, indicating that GRIM-19 may serve as a potential predictive factor and therapeutic target for CRC treatment.

The aim was to investigate the current status of esophageal endoscopy, including the evaluation of smoking and alcohol consumption, in Japan. A total of 47,441 patients who underwent 69,748 sessions of esophageal endoscopy were registered in the Japan Endoscopy Database between January 2015 and March 2017. The study variables were as follows: (1) methods for monitoring the esophagus and the time required for monitoring and (2) the status of smoking and alcohol consumption in patients with esophageal cancer and head and neck cancer. Image-enhanced endoscopy was performed in 10.6%, Lugol chromoendoscopy in 4.1%, and magnifying endoscopy in 3.2%. The mean time required for gastrointestinal endoscopy was 10 min 58 s. The mean examination times in patients with or without monitoring of the head and neck were 10 min 51 s and 11 min 13 s, respectively. In 57.0% of the patients with esophageal cancer, the head and neck were monitored at the time of gastrointestinal endoscopy. The proportion of current smokers (esophageal cancer: 16.8–4.7%; head and neck cancer: 24.3–9.3%) and addicted drinkers (esophageal cancer: 52.3–40.8%; head and neck cancer: 50.2–47.3%) were lower at the second or subsequent endoscopy than at the initial endoscopy. The new strategy for esophageal endoscopy has led to an evolutionary change in Japan. The patients with esophageal cancer and head and neck cancer who underwent a second or subsequent endoscopy had lower incidences of smoking and alcohol consumption, although the incidences remained high.

Background and aim Because the risk of colorectal cancer has not been well examined in fecal immunochemistry test (FIT)-positive patients who previously underwent colonoscopy, this study aimed to investigate this topic. Methods This was a single-center, observational study of prospectively collected data in Japan. FIT-positive, average-risk patients who underwent colonoscopy were divided into groups as follows: those who never underwent colonoscopy in the past (no colonoscopy group), those with a history of colonoscopy between 6 months and 5 years (0.5- to 5-year colonoscopy group), and those with a history of colonoscopy more than 5 years ago (> 5-year colonoscopy group). We investigated the prevalence of advanced neoplasia and invasive cancer among these groups using multiple logistic regression analysis. Results Detection rates of advanced neoplasia in the no colonoscopy group, 0.5- to 5-year colonoscopy group, and > 5-year colonoscopy group were 14.8% (240/1626), 3.9% (13/330), and 6.9% (17/248), respectively. Detection rates of invasive cancer in each aforementioned group were 5.7% (92/1,626), 0.3% (1/330), and 1.2% (3/248), respectively. Odds ratios of advanced neoplasia in the 0.5- to 5-year colonoscopy group and > 5-year colonoscopy were 0.23 (95% confidence interval [CI]: 0.13-0.42) and 0.40 (95% CI: 0.24-0.68), respectively, in multivariate analysis. The odds ratios of invasive cancer in each aforementioned group were 0.05 (95% CI: 0.01-0.37) and 0.19 (95% CI: 0.06-0.61), respectively. Conclusion Re-screening with the FIT should not be recommended for at least 5 years for average-risk patients after colonoscopy without high-risk neoplasms, because the risks of colorectal cancer are low in such patients.

Aim: To clarify whether antithrombotic drugs affect diagnosis using the immunochemical faecal occult blood test ­(iFOBT) of colorectal neoplasia. Methods: Using the Japan Endoscopy Database from 8 centres between 2015 and 2017, we analyzed data about patients who were iFOBT positive and had received direct oral anticoagulants (DOAC), warfarin, aspirin or thienopyridine. One-to-one matching-analogue propensity score weighted analyses were performed to compare the positive predictive value (PPV) of all neoplasms, invasive and non-invasive colorectal cancers and adenomas between drug users and non-users. All neoplasms included invasive and non-invasive colorectal cancer, and adenomas. Results: We analyzed 197 DOAC users and 196 non-users, 153 warfarin users and 153 non-users, 408 aspirin users and 415 non-users, and 97 thienopyridine users and 97 non-users. No significant differences were observed in the PPV for all neoplasms (56.67 vs. 50.43%), invasive cancer (4.32 vs. 3.53%), non-invasive cancer (15.58 vs. 15.56%) or adenoma (53.13 vs. 48.09%) between the DOAC user and non-user groups. No significant differences were observed in the PPV for all neoplasia, invasive and non-invasive cancer, or adenoma between warfarin, aspirin and thienopyridine use and non-users. Conclusions: DOAC, warfarin, aspirin and thienopyridine use did not decrease the PPVs of the iFOBT used to evaluate all colorectal neoplasia.

Background Underwater endoscopic mucosal resection (U-EMR) has emerged as an alternative technique for the resection of colorectal lesions. This study aimed to evaluate our initial experience using U-EMR. Methods This is a single-center, retrospective case series study. We analyzed the clinical outcomes of consecutive patients who underwent U-EMR in our endoscopy center, from December 2015 to February 2017. Results Our analysis included 64 lesions, contributed by 38 patients, with a mean age of 68.6 years (range, 25 to 90 years). The study sample included 33 right-sided and 25 left-sided colon lesions, and seven rectal lesions, with an average size of 16.2 mm (6 - 40 mm). Of these, 46 lesions were polypoid and 18 ones non-polypoid. Histologically, 31 lesions were low-grade adenomas, eight ones were high-grade adenomas, 11 were mucosal cancers, four were submucosal cancers, and 10 were classified as "others". En bloc resection was achieved in 52 (81%) lesions, with an en bloc resection rate of 95% for lesions < 20 mm and 55% for lesions ≥ 20 mm. Complete resection of neoplastic epithelial lesions, defined by a negative pathological margin, was achieved in 32 of 59 neoplastic epithelial lesions (54%). We identified three cases (5%) of post-procedural bleeding and one case of perforation (2%). Conclusions U-EMR can be feasibly used for resection of colonic lesions, including lesions ≥ 20 mm, although the en bloc resection rate for these lesions was lower than for lesions < 20 mm.

The advent of electronic medical records brought image filing systems to many hospitals, as well as electronic endoscopic medical records. However, data integration among multiple different vendors has not yet been accomplished. We start the Japan Endoscopic Database (JED) Project endorsed by Japan Gastroenterological Endoscopy Society (JGES) from January 2015. The purposes of this project are as follows: (i) developing the world's largest endoscopic database generated from daily use of the reporting system; (ii) capturing the actual performance of endoscopic practice in Japan; and (iii) standardizing the terminology and fundamental items for registry of clinical studies. Moreover, the JED project has the potential to automatically collect data about adverse events, competency and evaluation of residents, and actual numbers of procedures on a nationwide scale, certification for the specialty board system, and so on. We believe that this design paper will be helpful not only for future nationwide research but also for international research (UMIN000016093).

Background and Aim The Japan Endoscopy Database (JED) Project was started to develop the world's largest endoscopic database, capture the actual performance of endoscopic practice, and standardize the terminology and fundamental items needed for a clinical and research registry. This paper presents a progress report on the first phase of this project undertaken at eight endoscopic centers in Japan. Methods The list of data items to be collected was drafted by the MSED-J (Minimal Standard Endoscopic Database) subcommittee. These items were aggregated offline by integrating data from two endoscopic filing systems between July 2015 and December 2015. The study population included all patients who underwent esophagogastroduodenoscopy or colonoscopy at all eight centers, patients who underwent enteroscopy at five of the eight centers, and patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) at four of the eight centers. Results Data collected in this phase included 61 070 endoscopic procedures, of which 40 475 were esophagogastroduodenoscopies, 215 were enteroscopies, 19 204 were colonoscopies, and 1176 were ERCPs. Frequencies of complications were 0.68% for esophagogastroduodenoscopy, 0% for enteroscopy, 0.43% for colonoscopy, and 13.34% for ERCP. In addition, we obtained various data including Helicobacter pylori infection status, past history of endoscopy in patients who underwent enteroscopy or colonoscopy, and degree of difficulty of ERCP, although the frequencies of reporting were sometimes low, with some items