Endoscopic Diagnosis of Epithelial Subtypes of Superficial Non-Ampullary Duodenal Epithelial Tumors using Magnifying Narrow-Band Imaging.

INTRODUCTION: Superficial non-ampullary duodenal epithelial tumors (SNADETs) include low-grade adenoma (LGA) and high-grade adenoma or carcinoma (HGA/Ca) and are classified into two different epithelial subtypes, gastric-type (G-type) and intestinal-type (I-type). We attempted to distinguish them by endoscopic characteristics including magnifying endoscopy with narrow-band imaging (M-NBI). METHODS: Various endoscopic and M-NBI findings of 286 SNADETs were retrospectively reviewed and compared between G- and I-types and histological grades. M-NBI findings were divided into four patterns based on the following vascular patterns; absent, network, intrastructural vascular (ISV), and unclassified. Lesions displaying a single pattern were classified as mono-pattern and those displaying multiple patterns as mixed-pattern. Lesions showing CDX2 positivity were categorized as I-types and those showing MUC5AC or MUC6 positivity were categorized as G-types based on immunohistochemistry. RESULTS: Among 286 lesions, 23 (8%) were G-type and 243 (85%) were I-type. More G-type lesions were located oral to papilla (91.3 vs. 45.6%, p < 0.001), and had protruding morphology compared to those of I-types (65.2 vs. 14.4%, p < 0.001). The major M-NBI pattern was ISV in G-type (78.2 vs. 26.3%, p < 0.001), and absent for I-type (0 vs. 34.5%, p = 0.003). Three endoscopic characteristics; location oral to papilla, protruding morphology, and major M-NBI pattern (ISV) were independent predictors for G-type. Mixed-pattern was more common in HGA/Ca than LGA for I-type (77.0 vs. 58.8%, p = 0.01); however, there was no difference for those in G-type. CONCLUSION: Endoscopic findings including M-NBI are useful to differentiate epithelial subtypes.

Feasibility of Colorectal Endoscopic Submucosal Dissection in Elderly Patients: The Impact of Sarcopenia.

INTRODUCTION: Colorectal cancer is a public health concern associated with high incidence rates. Sarcopenia is a known risk factor for postoperative complications, although an association between increased complications after colorectal endoscopic submucosal dissection (ESD) and sarcopenia remains undocumented. Herein, we aimed to explore the feasibility of colorectal ESD in patients with sarcopenia. METHODS: This retrospective study included 499 patients (69 with and 430 without sarcopenia). We evaluated the short- and long-term outcomes of colorectal ESD. RESULTS: There were no significant differences between the two groups regarding en bloc, R0, or curative resection rates. However, poor bowel preparation was significantly more common in the sarcopenia group. Moreover, patients with sarcopenia exhibited a significant increase in complications (37.7% vs. 10.5%). Multivariate analysis revealed that sarcopenia (odds ratio [OR]: 3.78, 95% confidence interval [Cl]: 1.85-7.73, p < 0.001), anticoagulation therapy (OR: 3.59, 95% Cl: 1.86-6.92, p < 0.001), procedure time (OR: 1.28, 95% Cl: 1.11-1.47, p < 0.001), and resection size (OR: 1.25, 95% Cl: 1.03-1.52, p = 0.02) were significantly correlated with the Common Terminology Criteria for Adverse Events (CTCAE) ≥ grade 2. The correlation between sarcopenia and CTCAE ≥ grade 2 was maintained after matching, resulting in more extended hospital stays in patients with sarcopenia. However, we detected no association between sarcopenia and overall survival and ESD-related death. CONCLUSION: Sarcopenia is a risk factor for complications in colorectal ESD, suggesting that colorectal ESD could be performed for patients with sarcopenia, although much caution should be taken.

Factors Related to Delayed Adverse Events of Endoscopic Submucosal Dissection in the Duodenum.

INTRODUCTION: Endoscopic submucosal dissection for duodenal neoplasms (D-ESD) is considered a technically demanding procedure regarding the high risk of delayed adverse events. Data regarding optimal managements of ulcers after D-ESD are lacking. METHODS: A retrospective analysis was performed on consecutive 145 cases of D-ESD for superficial nonampullary duodenal epithelial tumors at a single referral center. Factors related to delayed adverse events and the healing process of ulcers after D-ESD were analyzed. RESULTS: Complete ulcer suture after D-ESD was performed in 128 cases (88%). Two delayed perforation occurred among cases with incomplete suture. Delayed bleeding occurred in 8 cases (6%) within 3 weeks. The ulcer closure rate at second-look endoscopy (SLE) was significantly low among cases with delayed bleeding (12.5% vs. 75%, p = 0.001). The bleeding rate before SLE was significantly high among patients who did not have complete ulcer closure after D-ESD (0.8% vs. 12%, p = 0.036). The ratio of lesions located in the second oral-Vater was significantly low among ulcers re-opened at SLE (38% vs. 14%, p = 0.044). Proton-pump inhibitors (PPIs) were administered for a median of 7 weeks (range 1-8 weeks). At 3 weeks, active ulcer stages were observed in a few cases, and healing or scarring was observed in most cases. CONCLUSIONS: Complete ulcer suture was related to decreased risk of delayed adverse events after D-ESD. From the bleeding period and healing process of D-ESD ulcers, the minimum required length of PPI may be 3 weeks after D-ESD.

Reduced DEFA5 Expression and STAT3 Activation Underlie the Submucosal Invasion of Early Gastric Cancers.

INTRODUCTION: Submucosal invasion is a core hallmark of early gastric cancer (EGC) with poor prognosis. However, the molecular mechanism of the progression from intramucosal gastric cancer (IMGC) to early submucosal-invasive gastric cancer (SMGC) is not fully understood. The objective of this study was to identify genes and pathways involved in the submucosal invasion in EGC using comprehensive gene expression analysis. METHODS: Gene expression profiling was performed for eight cases of IMGC and eight cases of early SMGC with submucosal invasion ≥500 µm. To validate the findings of gene expression analysis and to examine the gene expression pattern in tissues, immunohistochemical (IHC) staining was performed for 50 cases of IMGC and SMGC each. RESULTS: Gene expression analysis demonstrated that the expression levels of small intestine-specific genes were significantly decreased in SMGC. Among them, defensin alpha 5 (DEFA5) was the most downregulated gene in SMGC, which was further validated in SMGC tissues by IHC staining. Gene set enrichment analysis showed a strong association between SMGC, the JAK-STAT signaling pathway, and the upregulation of STAT3-activating cytokines. The expression of phosphorylated STAT3 was significant in the nucleus of tumor cells in SMGC tissues but not in areas expressing DEFA5. CONCLUSION: The results of this study strongly suggest that the downregulation of DEFA5 and the activation of STAT3 play a significant role in the submucosal invasion of EGC.

Diagnostic Performance of Endocytoscopy for Esophageal Eosinophilia.

INTRODUCTION: Eosinophils in the esophageal epithelium are unevenly distributed in eosinophilic esophagitis (EoE). Esophageal eosinophilia (EE) may be observable by endocytoscopy (EC). This study aimed to evaluate the diagnostic performance of EC for the diagnosis of EE. METHODS: A total of 33 EoE patients underwent EC with methylene blue staining from March 2020 to April 2021. A total of 194 EC images with corresponding biopsies were obtained. Three findings of EC, increased squamous cells (item I), increased inflammatory cells (item II), and cells with bilobed nuclei (item III), were established. These findings were reviewed by two endoscopists to diagnose EE. Another four endoscopists reviewed the images for interobserver agreement. RESULTS: When all three items were met by EC, the sensitivity and the accuracy for the diagnosis of EE were 88% and 76%, respectively. The integrated diagnostic odds ratios (ORs) for the diagnosis of EE of the four endoscopists were significant (OR: 3.98, 95% CI: 2.94-5.40, p < 0.001). The results were similar when only item III was met. Interobserver agreement was good for item III to diagnose EE (kappa value = 0.653). DISCUSSION/CONCLUSION: The diagnostic performance of EC for EE is acceptable and has good interobserver agreement. It may be useful for targeted biopsy in EoE patients.

Repeated steroid injection and polyglycolic acid shielding for prevention of refractory esophageal stricture.

BACKGROUND: Postoperative stricture and refractory stricture are severe adverse events which occur after expansive esophageal endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy of steroid injection, polyglycolic acid (PGA) shielding, and of additional steroid injection thereafter for the prevention of refractory esophageal stricture. METHODS: This is a retrospective cohort study of 816 consecutive cases of esophageal ESD performed between 2002 and 2021 at the University of Tokyo Hospital. After 2013, all patients with a diagnosis of superficial esophageal carcinoma covering over 1/2 the esophageal circumference underwent preventive treatment immediately after ESD with either "PGA shielding", "steroid injection", or "steroid injection + PGA shielding". Additional steroid injection was performed for high-risk patients after 2019. RESULTS: The risk of refractory stricture was especially high in the cervical esophagus (OR 24.77, p = 0.002) and after total circumferential resection (OR 894.04, p < 0.001). "Steroid injection + PGA shielding" was the only method significantly effective in preventing stricture occurrence (OR 0.36; 95% CI 0.15-0.83, p = 0.012). This method also decreased the risk of refractory stricture (OR 0.38; 95% CI 0.10-1.28, p = 0.096), but additional steroid injection was the only significantly effective method for prevention of refractory stricture (OR 0.42; 95% CI 0.14-0.98, p = 0.029). CONCLUSION: Combining steroid injection and PGA shielding is effective for preventing post-ESD stricture and refractory stricture. Additional steroid injection is a viable option for patients at high-risk for refractory stricture.

Scoring system for predicting the prognosis of elderly gastric cancer patients after endoscopic submucosal dissection.

OBJECTIVES: Comprehensive assessments of the long-term outcomes of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) in the elderly are unavailable. We aimed to create a scoring system to predict the long-term prognosis after ESD for EGC among patients aged ≥75 years. METHODS: We conducted retrospective studies of two cohorts: a single-center cohort (2006-2011) for developing the scoring system, and a multicenter cohort for validating the developed system (2012-2016). In the development cohort, factors related to death after ESD were identified using multivariable Cox regression analysis, and a predictive scoring system was developed. In the validation cohort, the scoring system was validated in 295 patients. RESULTS: In the development cohort, Charlson comorbidity index (CCI) ≥3 (hazard ratio [HR] 3.017), high psoas muscle index (PMI) (HR 2.206), and age ≥80 years (HR 1.978) were significantly related to overall survival after ESD. Therefore, high CCI, low PMI, and age ≥80 years were assigned 1 point each. The patients were categorized into low (≤1 point) and high (≥2 points) score groups based on their total scores. In the validation cohort, 184 and 111 patients were assigned to the low- and high-score groups, respectively. In comparisons based on Kaplan-Meier curves, the 5-year survival rate was 91.5% in the low-score group and 57.8% in the high-score group (log-rank test; P < 0.001). CONCLUSION: Our scoring system including high CCI, low PMI, and age ≥80 years could stratify the long-term prognosis of elderly patients aged ≥75 years after ESD for EGC.

Novel endoscopic approaches using the endocytoscopy for the target biopsy in esophageal eosinophilia.

BACKGROUND AND AIMS: Multiple biopsies are recommended for the diagnosis of eosinophilic esophagitis (EoE) because inflammatory changes are frequently patchy. Reports on EoE using endocytoscopy (ECS) are limited. This present study aimed to assess if diagnostic yield improves by adding ECS on conventional white light imaging (WLI) in patients with esophageal eosinophilia (EE). METHODS: A total of 284 biopsy specimens from 71 patients with a known diagnosis of EE were enrolled and divided into the WLI group (156 specimens) or the ECS group (128 specimens). Four biopsies from 5 and 10 cm proximal to the esophagogastric junction were taken from each patient. In the ECS group, the biopsy was performed where bilobed nuclei were observed. The biopsy sensitivity for EE, eosinophil count of a single specimen and the biopsy sensitivity of each endoscopic finding were evaluated between both groups. RESULTS: The sensitivity of a single biopsy specimen was higher in the ECS group than that of the WLI group (62.5 vs. 41.7%, P < 0.001). In addition, the median eosinophil count in the ECS group was significantly higher [19 vs. 6.5/high-power field (HPF), P < 0.001]. For each endoscopic finding, ECS-based biopsy had higher sensitivity than that of WLI in the diagnosis of edema (33.1 vs. 11.3%, P = 0.007) and linear furrows (75.8 vs. 52%, P = 0.005). CONCLUSION: This study showed that adding ECS to WLI improved the biopsy sensitivity and eosinophil detection in patients with EE.

Outcomes of endoscopic resection for superficial duodenal tumors: 10 years' experience in 18 Japanese high volume centers.

BACKGROUND: Data on endoscopic resection (ER) for superficial duodenal epithelial tumors (SDETs) are insufficient owing to their rarity. There are two main ER techniques for SDETs: endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). In addition, modified EMR techniques, such as underwater EMR (UEMR) and cold polypectomy, are becoming popular. We conducted a large-scale retrospective multicenter study to clarify the detailed outcomes of duodenal ER. METHODS: Patients with SDETs who underwent ER at 18 institutions from January 2008 to December 2018 were included. The rates of en bloc resection and delayed adverse events (AEs; defined as delayed bleeding or perforation) were analyzed. Local recurrence was analyzed using the Kaplan-Meier method. RESULTS: In total, 3107 patients (including 1017 undergoing ESD) were included. En bloc resection rates were 79.1 %, 78.6 %, 86.8 %, and 94.8 %, and delayed AE rates were 0.5 %, 2.2 %, 2.8 %, and 6.8 % for cold polypectomy, UEMR, EMR and ESD, respectively. The delayed AE rate was significantly higher in the ESD group than in non-ESD groups for lesions < 19 mm (7.4 % vs. 1.9 %; P < 0.001), but not for lesions > 20 mm (6.1 % vs. 7.1 %; P = 0.64). The local recurrence rate was significantly lower in the ESD group than in the non-ESD groups (P < 0.001). Furthermore, for lesions > 30 mm, the cumulative local recurrence rate at 2 years was 22.6 % in the non-ESD groups compared with only 1.6 % in the ESD group (P < 0.001). CONCLUSIONS: ER outcomes for SDETs were generally acceptable. ESD by highly experienced endoscopists might be an option for very large SDETs.

Changes in the gut microbiome in relation to the degree of gastric mucosal atrophy before and after Helicobacter pylori eradication.

OBJECTIVES: Helicobacter pylori infection causes atrophic gastritis, which affects the gut microbiome; the gastric acid concentration depends on the degree of atrophic gastritis. Helicobacter pylori eradication also affects gastric acidity. Here, we determined the differences in the post-eradication changes in the gut microbiome in relation to the progression of gastric atrophy. MATERIALS AND METHODS: Ten patients were included in the closed group and five in the open group, consisting of patients with non-progressive and progressive atrophy, respectively, diagnosed by endoscopy. The faecal microbiome was analysed and compared among three time-points: before eradication, 8 weeks after eradication, and 6 months after eradication. The microbiome was analysed by targeting 16S rRNA using Illumina Miseq. RESULTS: The relative abundance of 14 genera significantly differed between the closed and open groups before eradication, but only 12 and 6 genera presented a significant difference in the relative abundance at 8 weeks and 6 months after eradication, respectively. Of the 12 genera that differed between the closed and open groups before eradication, 8 genera, namely, Actinomyces, Aggregatibacter, Campylobacter, Granulicatella, Pyramidobacter, Streptococcus, Cardiobacterium, and Haemophilus, were oral-origin bacteria. Longitudinal changes showed that Haemophilus and Catenibacterium were consistently significantly more abundant in the open group than in the closed group during the follow-up period. CONCLUSION: The gut microbiome substantially differed depending on the progression of gastric atrophy, but this difference was decreased by eradication, especially the differences in the number of oral bacteria in the gut. Eradication therapy may improve dysbiosis that result from gastric atrophy.

Fecal microbiota transplantation in the treatment of irritable bowel syndrome: a single-center prospective study in Japan.

BACKGROUND: Fecal microbiota transplantation (FMT) is a potential treatment for irritable bowel syndrome (IBS), but its efficacy in Japanese IBS patients is unknown. This study aimed to evaluate the efficacy, side effects, and microbiome changes following FMT in Japanese IBS patients. METHODS: Seventeen Japanese patients with refractory IBS received FMT (4 donors) under colonoscopy. Responders were defined by an improvement in the IBS severity index (IBS-SI) of 50 points or more after 12 weeks. We evaluated the IBS-SI and Bristol Stool Form Scale (BSFS) and compared the diversity and microbiome before and 12 weeks after FMT. For the microbiome, we analyzed the V3-V4 region of the 16S rRNA gene. RESULTS: IBS-SI decreased an average of 115.58 points after 12 weeks, and 10 patients (58.8%) were considered responders. Eight patients with diarrhea (66.7%) and three patients with constipation (60.0%) showed improvement in the BSFS. Two patients complained of mild abdominal pain, but there were no cases with severe side-effects. α-diversity was increased only in the responder group (p = 0.017). Patients who closely paralleled the donor microbiome had a higher rate of IBS-SI improvement. The relative abundance of Neisseria and Akkermansia increased and Desulfovibrio and Delftia were decreased in the responder group after FMT. CONCLUSIONS: Following FMT, about 60% of Japanese patients with IBS showed improvement in both the IBS-SI and BSFS, without severe side effects. Increased α-diversity and similarity to the donor microbiome after FMT may be associated with better treatment effects. TRIAL REGISTRATION: This study was registered in the University Hospital Medical Information Network Clinical Trial Registration (UMIN000026363). Registered 31 May 2017, https://rctportal.niph.go.jp/s/detail/um?trial_id=UMIN000026363 . The study was registered prospectively.

Risk Factors for Non-Ampullary Duodenal Adenocarcinoma: A Systematic Review.

INTRODUCTION: An increase in the incidence of duodenal adenocarcinoma has been recently reported. However, little is known about the risk factors for duodenal adenocarcinoma, which are important for screening purposes. We, therefore, aimed to conduct a systematic review to identify risk factors for non-ampullary duodenal adenocarcinoma. METHODS: A medical literature search was performed using electronic databases, including PubMed, Cochrane Library, Japan Medical Abstracts Society, and Web of Science. Studies that assessed the association between dietary habits, lifestyle behaviors, comorbidities, and non-ampullary duodenal adenocarcinoma were extracted. The Newcastle-Ottawa Scale was used to assess the risk of bias in individual studies, and the Grading of Recommendations, Assessment, Development, and Evaluations approach was used to assess the quality of evidence across studies included in this review. RESULTS: Out of 1,244 screened articles, 10 were finally selected for qualitative synthesis. In the general population, no consistent risk factors were identified except for Helicobacter pylori positivity, which was considered a risk factor in 2 studies, but the quality of evidence was considered very low because of the high risk of bias. In patients with familial adenomatous polyposis (FAP), Spigelman stage IV at initial endoscopy was considered a consistent risk factor in 3 studies. CONCLUSIONS: There are currently limited data regarding risk factors for non-ampullary duodenal adenocarcinoma, and no conclusive risk factors were identified in the general population. However, in patients with FAP, Spigelman stage IV was identified as a consistent risk factor. Further studies are needed to improve diagnosis and support effective clinical management of this malignancy.

Artificial intelligence-based diagnosis of upper gastrointestinal subepithelial lesions on endoscopic ultrasonography images.

BACKGROUND: Endoscopic ultrasonography (EUS) is useful for the differential diagnosis of subepithelial lesions (SELs); however, not all of them are easy to distinguish. Gastrointestinal stromal tumors (GISTs) are the commonest SELs, are considered potentially malignant, and differentiating them from benign SELs is important. Artificial intelligence (AI) using deep learning has developed remarkably in the medical field. This study aimed to investigate the efficacy of an AI system for classifying SELs on EUS images. METHODS: EUS images of pathologically confirmed upper gastrointestinal SELs (GIST, leiomyoma, schwannoma, neuroendocrine tumor [NET], and ectopic pancreas) were collected from 12 hospitals. These images were divided into development and test datasets in the ratio of 4:1 using random sampling; the development dataset was divided into training and validation datasets. The same test dataset was diagnosed by two experts and two non-experts. RESULTS: A total of 16,110 images were collected from 631 cases for the development and test datasets. The accuracy of the AI system for the five-category classification (GIST, leiomyoma, schwannoma, NET, and ectopic pancreas) was 86.1%, which was significantly higher than that of all endoscopists. The sensitivity, specificity, and accuracy of the AI system for differentiating GISTs from non-GISTs were 98.8%, 67.6%, and 89.3%, respectively. Its sensitivity and accuracy were significantly higher than those of all the endoscopists. CONCLUSION: The AI system, classifying SELs, showed higher diagnostic performance than that of the experts and may assist in improving the diagnosis of SELs in clinical practice.

Comparison of Endoscopic Ultrasonography and Conventional Endoscopy for Prediction of Tumor Depth in Superficial Nonampullary Duodenal Epithelial Tumors.

BACKGROUND: The utility of endoscopic ultrasonography (EUS) in predicting tumor depth among superficial nonampullary duodenal epithelial tumors (SNADETs) is unclear. The aim was to compare EUS with conventional endoscopy (CE) for the evaluation of tumor invasion of SNADETs. METHODS: A retrospective analysis was performed on consecutive 174 lesions/169 patients with duodenal dysplasia or adenocarcinoma with invasion up to submucosa who underwent both CE and EUS before endoscopic (n = 133) or surgical (n = 41) treatment. Endoscopic staging by CE was performed based on the characteristic endoscopic criteria of submucosal invasion (irregular surface, submucosal tumor [SMT]-like marginal elevation, and fusion of converging folds). The diagnostic performance of each test was compared with the final histology. RESULTS: The sensitivity and accuracy of estimating the depth were higher for CE compared to that of EUS (99.4% vs. 89.4%, p < 0.01 and 97.7% vs. 87.9%, p < 0.01, respectively). Univariate analysis of endoscopic factors revealed that tumor diameter, red color, SMT-like appearance, and hypoechogenicity were factors related to advanced histology. Multivariate analysis revealed that the presence of SMT-like appearance based on CE was an independent factor to predict submucosal invasion (p = 0.025). Gross morphology of the combined type was associated to incorrect diagnosis of EUS (p = 0.007). Among 3 cases in which EUS overestimated the tumor depth, carcinoma extension in submucosal Brunner's gland or nontumorous submucosal cystic dilation was observed. CONCLUSION: EUS may not be necessary, and CE may be sufficient for determining the optimal therapeutic strategy for SNADETs.

Preliminary Comparison of Endoscopic Brush and Net Catheters as the Sampling Tool to Analyze the Intestinal Mucus in the Rectum with Ulcerative Colitis Patients.

BACKGROUND: The pathophysiology of ulcerative colitis (UC) remains unclear, but early lesions on the colorectal mucosal surface may play an important role in its etiology. Intestinal mucus samples, including inner and outer layers, are collected by net or brush catheters, but the quality of the samples obtained by each method has not been fully investigated. OBJECTIVE: The purpose of this study was to compare the microbiome and protein content of intestinal mucus collected by net and brush catheters during colonoscopy. METHODS: Intestinal mucus samples from the lower rectum of 4 patients with UC were collected using a net catheter, a brush catheter, and intestinal fluid suction. Microbiome and protein content were analyzed using 16S rRNA gene sequencing and mass spectrometry. RESULTS: The patients demonstrated significant differences in microbiome alpha diversity (p < 0.05), but this difference was not observed between the sampling methods. Net catheter samples demonstrated higher total protein concentrations than brush catheter samples. The brush catheter group had more Lachnospira, a butyrate-producing bacterium, when compared to the net group. The brush catheter group also had more oral bacteria of Staphylococcus and Dialister in those with active phase when compared to the net group. CONCLUSIONS: Brush catheters are more likely to collect the intestinal mucus inner layer, whereas net catheters are more likely to collect larger samples that include the outer mucus layer, as well as the intestinal fluid. Two sampling methods with different types of collection of the mucosa may lead to different results among patients with mucosal vulnerabilities.

Network Analysis of Gut Microbiota Including Fusobacterium and Oral Origin Bacteria and Their Distribution on Tumor Surface, Normal Mucosa, and in Feces in Patients with Colorectal Cancer.

INTRODUCTION: Fusobacterium and several bacteria are reported to be associated with colorectal cancer (CRC). However, their relationship and whether they cause CRC or are just adapted to the cancerous environment is not known. We approached this subject by investigating the correlation and distribution of the bacteria throughout the colon in patients with CRC and elucidated the relationship between microbiota and CRC. METHODS: Twenty-five patients with CRC who underwent colonoscopy for endoscopic submucosal dissection or surgery were prospectively enrolled. Fecal samples were taken before bowel preparation, and mucosal samples were collected from three sites (tumor surface, tumor-adjacent mucosa, and cecum) during colonoscopy using a cytology brush. The microbiota was identified and analyzed by sequencing of the 16S rRNA gene of the V3-V4 region. We evaluated the correlation between the bacteria based on network analysis and the distribution of Fusobacterium in the colon. RESULTS: A network consisting of many bacteria was found in all sites; especially, oral origin bacteria including Fusobacterium formed a positively correlated network on tumor surface. Streptococcus showed a significantly higher relative abundance on tumor surface than in feces. The relative abundance of Fusobacterium had significant positive correlations between tumor surface and feces, tumor-adjacent mucosa, and cecum. CONCLUSION: In patients with CRC, many bacteria were correlated with each other, and Fusobacterium and oral origin bacteria formed a positively correlated network on tumor surface. Fusobacterium was equally distributed on tumor surface and throughout the lumen and mucus in the colon. In the colon where Fusobacterium is widely distributed, Fusobacterium would adhere to the tumor surface and be correlated with oral origin bacteria to make a microenvironment that is favorable for CRC.

Cold snare polypectomy for superficial non-ampullary duodenal epithelial tumor: a prospective clinical trial (pilot study).

BACKGOUND: Cold snare polypectomy (CSP) can minimize the risk of adverse events and has become a standard treatment for small colorectal polyps. CSP might also be suitable for small superficial non-ampullary duodenal epithelial tumors (SNADETs). This study aimed to evaluate the safety of CSP for SNADETs. METHODS: The major indication criteria were as follows: (1) endoscopically diagnosed SNADET, (2) ≤ 10 mm, and (3) a single primary lesion. CSP was performed using an electrosurgical snare without electrocautery. Follow-up endoscopy and scar biopsy were performed 3 months after CSP. The primary endpoint was the delayed adverse events rate. RESULTS: In total, 21 patients were enrolled. Two and 19 lesions were located in the duodenal bulb and 2nd portion, respectively; the median lesion size was 8 mm. CSP was attempted for all lesions; three lesions could not be resected without electrocautery and were removed by conventional endoscopic mucosal resection (EMR). The rate of spurting bleeding after CSP was 0%. The median procedure time was 12 min, the median resected specimen size was 12 mm, and the rate of en bloc resection was 81% (17/21). No adverse events were observed intraoperatively, with no delayed adverse events after CSP. Histopathology revealed 15 adenomas, 4 cancers (intramucosal), and 2 non-neoplastic lesions. The horizontal margins were negative/positive/undetermined in 9, 1, and 11 cases, respectively. All vertical margins were negative. Only one recurrence was detected by follow-up endoscopy 3 months after CSP. CONCLUSIONS: CSP can be performed safely for small SNADETs. CLINICAL TRIAL REGISTRATION: This trial was registered with the University Hospital Medical Information Network Clinical Trials Registry ( http://www.umin.ac.jp/ctr/index.htm ), and the registration number is UMIN000019157.

Influence of hospital volume on bleeding after endoscopic submucosal dissection for early gastric cancer in Japan: a multicenter propensity score-matched analysis.

BACKGROUND: Information on whether there is a relationship between hospital volume and bleeding after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is limited. This study aimed to compare the bleeding rates after ESD for EGC according to the hospital volume. METHODS: Patients who underwent ESD for EGC at 33 institutions in Japan between November 2013 and October 2016 were included in this multicenter retrospective study. Hospital volume was categorized into three groups, based on the average annual number of ESD procedures: low- and medium-volume group (LMVG), high-volume group (HVG), and very high-volume group (VHVG). The bleeding rate after ESD for EGC was compared between the three hospital volume groups after propensity score matching. RESULTS: A total of 10,320 patients, including 2797 patients in the LMVG, 4646 patients in the HVG, and 2877 patients in the VHVG, were identified. Propensity score matching yielded 2002 patients in each hospital volume group, with an improved balance of confounding variables between the three groups. The bleeding rates in the LMVG, HVG, and VHVG were 4.3%, 3.7%, and 4.9%, respectively, and no significant difference was noted between the three groups. CONCLUSIONS: The bleeding rate after ESD for EGC did not differ between hospitals in Japan. The finding indicated that ESD for EGC is equally feasible across Japanese hospitals of different volumes regarding bleeding after ESD.

Effects of steroid use for stenosis prevention after endoscopic submucosal dissection for cervical esophageal cancer.

BACKGROUND AND AIM: Esophageal stenosis is a serious complication after endoscopic submucosal dissection (ESD) for thoracic esophageal cancer (TEC), and steroid has been applied for stenosis prevention. However, the rate of stenosis and effect of steroid for ESD of cervical esophageal cancer (CEC) remain unknown. The aim was to clarify the rate and managements of post-ESD stenosis for CEC. METHODS: A total of 325 lesions with 272 patients who underwent ESD for esophageal cancers were enrolled and were divided to the CEC group (43 lesions) or the TEC group (282 lesions). Patient characteristics, clinicopathological features, procedure-related outcomes of esophageal ESD, stenosis rate and clinical outcome of steroid use cases were evaluated. RESULTS: More patients in the CEC group received preventive steroid treatment compared to the TEC group (37.2% vs 14.5%, P = 0.001). The rate of post-ESD stenosis tended to be higher in the CEC group (11.6%) than in the TEC group (6.7%). For cases of 3/4 ≤ of circumference, local injection with oral steroid had lower stenosis rate than local injection only in both groups (CEC 40% vs 100%, TEC 30.7% vs 56.3%). More sessions and longer duration of dilation were needed to release the stenosis in the CEC group (20 times vs. 5 times, P = 0.015; 196 days vs. 55 days, P = 0.043). CONCLUSION: The post-ESD stenosis rate of CEC tended to be higher than that of TEC. More intensive preventive measures for post-ESD stenosis may be needed for CEC than TEC.

Endoscopic management of perihilar cholangiocarcinoma.

Endoscopic management for perihilar cholangiocarcinoma (PHCC) is evolving toward more accurate diagnosis and safer drainage. In imaging, it is important to diagnose the entire lesion using multidetector-row computed tomography to determine resectability and optimal surgical planning, followed by local diagnosis using endoscopic retrograde cholangiopancreatography. Video peroral cholangioscopy and probe-based confocal laser endomicroscopy have been newly introduced as diagnostic imaging methods and are being applied clinically. In transpapillary forceps biopsy for PHCC diagnosis, the location in the bile duct (for mapping biopsy) and the number of biopsy samples should be determined depending on resectability, the morphological type, and future surgical planning. Preoperative drainage has shifted from percutaneous transhepatic biliary drainage to endoscopic nasobiliary drainage given the possibility of seeding metastasis. In addition, considering potential patient discomfort from a nasal tube, the usefulness of the placement of a plastic stent above the papilla (inside stent) as a bridging therapy for surgery has been reported. For drainage of unresectable PHCC, the improved prognosis due to advances in chemotherapy has necessitated a strategy that accounts for reintervention. Thus, in addition to uncovered self-expandable metallic stents (SEMS), exchangeable slim fully covered SEMS and inside stents have started to be used. In addition to the conventional transpapillary approach, an endoscopic ultrasonography-guided approach has been introduced, and a combination of both methods has also been proposed. To improve the quality of life and prognosis of PHCC patients, endoscopists need to understand and be able to use the various methods of endoscopic management for PHCC.