Characteristics of Gastric Mucosa-Associated Microbiota in Patients with Early Gastric Cancer After Successful Helicobacter pylori Eradication.

BACKGROUND: Helicobacter pylori (H. pylori) is widely recognized as a definite carcinogen in gastric cancer (GC). Although H. pylori eradication reduces the risk of GC, GC recurrence has been detected even after successful H. pylori eradication. Recently, the analysis of gut microbiota was reported. AIMS: This study aimed to evaluate the correlation between gastric mucosa-associated microbiota (G-MAM) and early gastric cancer (EGC) after successful H. pylori eradication. METHODS: In this pilot study, G-MAM were collected during the esophagogastroduodenoscopy of 17 patients, receiving H. pylori eradication therapy at least 5 years ago. The patients were divided into those with EGC (the EGC group, 8 patients) and those without EGC (the NGC group, 9 patients). Microbial samples in the greater curvature of the pyloric site were obtained using an endoscopic cytology brush, and the G-MAM profiles of each sample were analyzed using 16S rRNA V3-V4 gene sequencing. RESULTS: Between the two groups, there was no significant difference in the median age, sex, median period after successful eradication of H. pylori, the α diversity, and the average abundance at the phylum level. At the genus level, the average abundance of Unclassified Oxalobacteraceae, Capnocytophaga, and Haemophilus was significantly lower in the EGC group than in the NGC group (0.89 vs. 0.14%, P < 0.01, 0.28 vs. 0.00%, P < 0.01 and 5.84 vs. 2.16%, P = 0.034, respectively). CONCLUSIONS: We demonstrated alternations in the profiles of G-MAM between the two groups. Our results suggest that G-MAM may influence carcinogenesis after successful H. pylori eradication.

Efficacy of endoscopic ultrasound-guided pelvic abscess drainage for pelvic abscesses: A case series study.

BACKGROUND AND STUDY AIM: This is a retrospective study to evaluate the safety and efficacy of endoscopic ultrasound-guided pelvic abscess drainage (EUS-PAD) in a single hospital setting. PATIENTS AND METHODS: The referral criteria for EUS-PAD included patients with a pelvic abscess (PA) that was amenable for the procedure. A total of 14 patients with PA treated with EUS-PAD were included in this study. The mean patient age was 57.4 years, and male-to-female ratio was 7:7. Overall, there were six cases of appendiceal perforation, five of rectal cancer and one case each of the diverticular perforation, perianal abscess, and walled-off necrosis. RESULTS: Overall, 100% of procedures were successful. Clinical success was achieved in 11 patients and they were discharged after EUS-PAD within 21.4 days on an average and the average duration of stent placement before removal was 27.0 days. Of all, six patients achieved complete improvement status where the cause was appendiceal perforation while two and one of the patients were recovered where the causes were post-curative operation for carcinoma and walled-off necrosis, respectively. Eight out of eleven patients who exhibited appendiceal perforation or underwent radical rectal cancer surgery were discharged after an average of 9.4 days post EUS-PAD. Although two patients showed temporary improvement, with perianal abscess and controlled rectal carcinoma, the PA worsened as the primary disease intensified. The PA drainage was ineffective in three patients where two of them had uncontrolled rectal cancer and one had diverticular perforation. CONCLUSION: Conclusively, the EUS-PAD is not only a reliable, safe, and efficient alternative to surgical and percutaneous drainage but also a valuable procedure with a high success rate for patients with acute infections, such as those who have had an appendiceal perforation or curative surgery. Poor indications and contraindications for EUS-PAD include uncontrolled gastrointestinal perforation and direct tumor invasion.

Demarcation Line Determination for Diagnosis of Gastric Cancer Disease Range Using Unsupervised Machine Learning in Magnifying Narrow-Band Imaging.

BACKGROUND AND AIMS: It is important to determine an accurate demarcation line (DL) between the cancerous lesions and background mucosa in magnifying narrow-band imaging (M-NBI)-based diagnosis. However, it is difficult for novice endoscopists. We aimed to automatically determine the accurate DL using a machine learning method. METHODS: We used an unsupervised machine learning approach to determine the DLs. Our method consists of the following four steps: (1) an M-NBI image is segmented into superpixels using simple linear iterative clustering; (2) the image features are extracted for each superpixel; (3) the superpixels are grouped into several clusters using the k-means method; and (4) the boundaries of the clusters are extracted as DL candidates. The 23 M-NBI images of 11 cases were used for performance evaluation. The evaluation investigated the similarity of the DLs identified by endoscopists and our method, and the Euclidean distance between the two DLs was calculated. For the single case of 11 cases, the histopathological examination was also conducted to evaluate the proposed system. RESULTS: The average Euclidean distances for the 11 cases were 10.65, 11.97, 7.82, 8.46, 8.59, 9.72, 12.20, 9.06, 22.86, 8.45, and 25.36. The results indicated that the proposed method could identify similar DLs to those identified by experienced doctors. Additionally, it was confirmed that the proposed system could generate pathologically valid DLs by increasing the number of clusters. CONCLUSIONS: Our proposed system can support the training of inexperienced doctors as well as enrich the knowledge of experienced doctors in endoscopy.

Linked Color Imaging and Blue Laser Imaging for the Diagnosis of Superficial Non-Ampullary Duodenal Epithelial Tumors.

BACKGROUND AND OBJECTIVE: This study aimed to evaluate endoscopic findings using linked color imaging (LCI) and blue laser imaging (BLI) and to determine a diagnostic predictor for duodenal adenocarcinomas. METHODS: All consecutive patients who underwent endoscopic resection for superficial non-ampullary duodenal epithelial tumors (SNADETs) between October 2012 and June 2019 were enrolled in this study. Two highly experienced endoscopists investigated six morphological findings using both white light imaging and LCI and three magnifying endoscopic findings using magnifying BLI (M-BLI). RESULTS: A total of 90 patients with 110 SNADETs, including 87 adenocarcinomas and 23 adenomas, were analyzed in this study. Among the non-magnifying endoscopic findings, the presence of reddish color, orange color on LCI (orange color sign), lobulation, depression, and marginally white opaque substance were found significantly more frequently in adenocarcinomas than in adenomas (p = 0.015, p < 0.001, p = 0.048, p < 0.001, and p = 0.007, respectively). Among the magnifying endoscopic findings, a mixed microsurface pattern (MSP), irregular MSP, and irregular microvascular pattern were found significantly more frequently in adenocarcinomas than in adenomas (p < 0.001, p < 0.001, and p = 0.002, respectively). In the multivariate analysis of all endoscopic findings associated with adenocarcinoma, orange color sign (odds ratio [OR] 10.46; 95% confidence interval [CI]: 1.42-77.08; p = 0.021), mixed MSP (OR 4.66; 95% CI: 1.02-21.40; p = 0.048), and irregular MSP (OR 13.11; 95% CI: 1.41-121.99; p = 0.024) were independent predictors of adenocarcinoma. CONCLUSIONS: The presence of orange color sign on LCI and mixed/irregular MSP on M-BLI were independent diagnostic predictors that were frequently observed in duodenal adenocarcinoma.

Enhanced Visibility in Evaluating Gastric Cancer and Helicobacter pylori-Associated Gastritis Using Linked Color Imaging with a Light-Emitting Diode Light Source.

BACKGROUND: In Japan, laser light source (Laser) endoscopy is widely available, and the characteristics of light-emitting diode light source (LED) endoscopy have not been clarified. AIMS: We assessed the visibility of early gastric cancers (EGCs) and Helicobacter pylori (H. pylori)-associated gastritis for LED endoscopy compared with laser endoscopy using white-light imaging (WLI) and linked color imaging (LCI). METHODS: We assessed 99 lesions between February 2019 and March 2020. The visibility was scored from four (excellent visibility) to one (poor visibility) by evaluating videos including EGCs and gastric mucosa captured using WLI and LCI with LED endoscopy (LED-WLI and LED-LCI, respectively) and laser endoscopy (Laser-WLI and Laser-LCI, respectively). The primary end point was the non-inferiority of the visibility of EGCs and H. pylori-associated gastritis between LED-/Laser-WLI and LED-/Laser-LCI. RESULTS: The visibility scores of EGCs for LED-/Laser-WLI and LED-/Laser-LCI were 3.14/2.97 and 3.39/3.35, respectively. The visibility scores of H. pylori-associated gastritis [intestinal metaplasia (IM), diffuse redness (DR), regular arrangement of collecting venules (RAC) and map-like redness (MR)] for LED-/Laser-WLI and LED-/Laser-LCI were 3.05/2.85 and 3.60/3.50 (IM), 2.76/2.50 and 2.96/2.86 (DR), 2.69/2.44 and 2.77/2.62 (RAC) and 2.97/2.75 and 3.39/3.27 (MR). Non-inferiority was demonstrated for visualizing EGCs and H. pylori-associated gastritis. CONCLUSIONS: LED-WLI and LED-LCI can be used to visualize EGCs and H. pylori-associated gastritis with non-inferiority to Laser-WLI and Laser-LCI. Furthermore, even with LED, LCI was more effective than WLI for evaluating EGCs and H. pylori-associated gastritis. Therefore, LED endoscopy can be used to detect EGCs and evaluate H. pylori-associated gastritis accurately.

Deoxycholic acid delays the wound healing of colonic epithelial cells via transmembrane G-protein-coupled receptor 5.

BACKGROUND AND AIM: Efficient intestinal wound healing is essential for good prognoses of ulcerative colitis (UC). Although bile acids and the transmembrane G-protein-coupled receptor (TGR) 5 have been reported to affect wound healing in intestinal epithelial cells, the detailed underlying mechanisms are unclear. Here, we investigated the role of TGR5 in wound healing in the context of colonic epithelial cells in the presence of bile acids. METHODS: The expression of TGR5 in the colonic epithelium of both a dextran sulfate sodium (DSS)-induced colitis mouse model (recovery phase), and UC patients in clinical remission, was evaluated. Young adult mouse colonic epithelial (YAMC) cells were then used to evaluate wound healing after treatment with deoxycholic acid (DCA); TGR5 was silenced in YAMC cells via shRNA-transfection, and a wound-healing assay in the presence of DCA was performed. Furthermore, we investigated the role of the activation of AKT in the context of wound healing. RESULTS: The expression of TGR5 was decreased in the colonic epithelium of both mice with DSS-induced colitis and UC patients. Additionally, DCA significantly delayed wound healing in YAMC cells but not in TGR5 silenced ones. Of note, the DCA-induced activation of AKT signaling in YAMC cells was inhibited by TGR5 silencing, and AKT inhibitors prevented the wound healing delay induced by DCA. CONCLUSIONS: Overall, we show that DCA delays wound healing in the context of colonic epithelial cells through AKT activation. These results may support the development of new therapeutic approaches for epithelial regeneration in UC.

Blue laser imaging identifies endoscopic findings corresponding to metachronous esophageal squamous cell carcinoma.

BACKGROUND AND STUDY AIM: This study aimed to evaluate endoscopic findings using non-magnifying blue laser imaging (BLI) to determine the risk factors for metachronous esophageal squamous cell carcinoma (ESCC). PATIENTS AND METHODS: All consecutive patients who underwent endoscopic submucosal dissection (ESD) for primary superficial ESCC (SESCC) without a history of ESCC between January 2013 and January 2016 were enrolled. Three highly experienced endoscopists investigated seven endoscopic findings using non-magnifying BLI as follows: (1) a brownish area with unclear margin, (2) white flat deposits, (3) multiple foci of dilated vessels, (4) low capillary permeability, (5) multiple glycogenic acanthosis, (6) horizontal lines, and (7) a nonuniform color tone. Furthermore, Lugol-voiding lesions (LVLs) were graded according to the number of LVLs per endoscopic view (A, no lesions; B, 1-9 lesions; C, ≥ 10 lesions). RESULTS: A total of 102 SESCC patients who underwent ESD were included. Multivariate analyses showed that multiple foci of dilated vessels, low capillary permeability, and a nonuniform color tone were significantly associated with metachronous ESCC (hazard ratio [HR] 2.30; 95% confidence interval [CI] 1.01-5.46; P = 0.049, HR 5.25; 95% CI 1.86-15.01; P = 0.002 and HR 3.17; 95% CI 1.11-9.43; P = 0.032, respectively). The three-year cumulative incidence of metachronous ESCC was significantly higher in patients with low capillary permeability and a nonuniform color tone than in patients without these findings. (41.1% vs. 6.0%, 45.0% vs. 12.7%, respectively, P < 0.001 for both). CONCLUSION: BLI findings of multiple foci of dilated vessels, low capillary permeability, and a nonuniform color tone in the background esophageal mucosa were risk factors for patients with metachronous ESCC after ESD.

Effects of the combined use of a scissor-type knife and traction clip on endoscopic submucosal dissection of colorectal tumors: a propensity score-matched analysis.

Background and study aims This study evaluated the technical aspects of colorectal endoscopic submucosal dissection (ESD) with the Clutch Cutter (CC) (Fujifilm Co., Tokyo, Japan), a scissor-type knife, and the S-O clip (SO) as a traction clip, and compared the safety and efficacy to ESD using a needle-type knife. Patients and methods This was a single-center retrospective study. In Study 1, we evaluated 125 ESD patients: 60 using the SO and CC (SO group) and 65 using the CC (CC group). In Study 2, we evaluated 185 ESD patients: the CC group (N = 65) and 120 using the Flush knife BT-S (Flush group) (Fujifilm Co., Tokyo, Japan). In both studies, the clinicopathological features and therapeutic outcomes were compared using a propensity score-matched analysis. Results In 36 pairs of matched patients in Study 1, the rates of en bloc resection, R0 resection, perforation, and postoperative bleeding (POB) were 97.2 %, 88.9 %, 2.8 %, and 0 %, respectively, for the SO group and 100 %, 91.7 %, 0 %, and 0 % for the CC group (not significant). The mean procedure time for the SO group among less-experienced endoscopists was significantly shorter than in the CC group (42 vs. 65 minutes, P  = 0.036). In 49 pairs of matched patients in Study 2, the rates of en bloc resection, R0 resection, perforation, and POB were 100 %, 95.8 %, 0 %, and 0 %, respectively, for the CC group and 98.0 %, 95.8 %, 0 %, and 2.0 % for the Flush group (not significant). The mean procedure time in the CC group among less-experienced endoscopists was significantly shorter than in the Flush group (52 vs. 67 minutes, P  = 0.038). Conclusions CC and the combined use of CC and SO reduced colorectal ESD procedure time among less-experienced endoscopists.

Improved Visibility of Early Gastric Cancer after Successful Helicobacter pylori Eradication with Image-Enhanced Endoscopy: A Multi-Institutional Study Using Video Clips.

The visibility and diagnostic accuracy of early gastric cancer (EGC) after Helicobacter pylori (HP) eradication have been reported to improve using image-enhanced endoscopy (IEE) compared with white light imaging (WLI). The present study clarified the appropriate IEE for the detection and diagnosis of EGC in clinical settings. This prospective and cross-sectional study evaluated the visibility of EGC and endoscopic findings of gastric mucosa after successful HP eradication (n = 31) using videos with WLI and IEE. Three endoscopists evaluated high-definition videos in a randomized order. The mean visibility scores (MVSs) on linked color imaging (LCI) for atrophic border, intestinal metaplasia, map-like redness, and EGC were the highest among each modality (3.87 ± 0.34, 3.82 ± 0.49, 3.87 ± 0.50, and 3.35 ± 0.92, respectively). The MVSs with blue laser imaging (BLI) were highest for magnifying view of the demarcation line (DL), microsurface pattern (MSP), and microvascular pattern (MVP) for EGC (3.77 ± 0.49, 3.94 ± 0.25, and 3.92 ± 0.34, respectively). LCI had the highest visibility among findings of gastric mucosa and EGC after HP eradication, and BLI had the highest visibility of MVP, MSP, and DL in magnifying observation. These results suggest that LCI observation in the entire stomach and further magnifying BLI are the best methods for detecting and diagnosing EGCs after HP eradication, respectively.

Effects of Guidelines for Gastroenterological Endoscopy in Patients Undergoing Antithrombotic Treatment on Postoperative Bleeding after Endoscopic Submucosal Dissection for Early Gastric Cancer: A Propensity Score-Matching Analysis.

BACKGROUND: Management of antithrombotic agents during endoscopic treatment changed after the publishing of -Japan Gastroenterological Endoscopy Society guidelines for gastroenterological endoscopy in antithrombotic drug users (GL-2012). OBJECTIVES: We aimed to evaluate the effect of implementing antithrombotic agent management guidelines (GL-2012) on postoperative bleeding after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) and on the prevention of thromboembolic events. METHODS: A total of 1,264 patients who underwent ESD for EGC at Kyoto Prefectural University Hospital between June 2002 and March 2017 were enrolled and divided into 2 groups: 621 patients before the publication of GL-2012 (Pre-GL group) and 643 patients after (Post-GL group). Relationships between postoperative bleeding and various clinicopathological factors in each group were investigated through propensity score-matching analysis. RESULTS: In the Pre-GL group, antihypertensive agent use (p < 0.01) and upper third of the stomach (p < 0.01) were significantly related to postoperative bleeding in univariate analysis. Antihypertensive agent use (OR 4.6, 95% CI 1.6-12.8) and upper third of the stomach (OR 4.9, 95% CI 1.8-13.4) were significantly related to postoperative bleeding in multivariate analysis. In the Post-GL group, antihypertensive agent use (p < 0.01), dual antiplatelet agents use (p < 0.01), anticoagulant agents use (p < 0.01), and heparin replacement therapy (p < 0.01) were significantly related to postoperative bleeding in univariate analysis. Antihypertensive agent use (OR 3.4, 95% CI 1.1-9.6), dual antiplatelet agents (OR 12.3, 95% CI 2.4-63.0), and heparin replacement therapy (OR 10.2, 95% CI 2.5-41.5) were significantly related to postoperative bleeding in multivariate analysis. CONCLUSIONS: The adherence to GL-2012 might reduce risk of thromboembolic events. On the other hand, dual antiplatelet agents therapy and heparin replacement therapy were the new independent risk factors for ESD postoperative bleeding in EGC after GL-2012. Especially as for heparin replacement therapy, uninterrupted warfarin or a temporary short interruption of direct oral anticoagulants without heparin replacement therapy might be recommended rather than heparin replacement therapy.

Diagnostic Ability of Magnifying Blue Light Imaging with a Light Emitting Diode Light Source for Early Gastric Cancer: A Prospective Comparative Study.

INTRODUCTION: An innovative endoscopic system using 4-color light-emitting diodes (LED) was released between 2016 and 2017 in locations that had not approved laser endoscopes for use, including the United States and Europe. OBJECTIVE: This study compared the diagnostic efficacy between magnifying blue light imaging with an LED light source (LED-BLI) and magnifying blue laser imaging with a laser light source (Laser-BLI) for early gastric cancer (EGC). METHODS: In this prospective, single-center, noninferiority study, 80 gastric lesions were evaluated between January 2017 and July 2017. The magnifying findings of gastric lesions - including the demarcation line (DL), microvascular pattern (MVP), and microsurface pattern (MSP) - were evaluated using Laser-BLI and LED-BLI according to the vessel plus surface classification system (VSCS). The primary end point was to determine whether the diagnostic accuracy of LED-BLI for EGC was noninferior to that of conventional Laser-BLI. RESULTS: Overall, we evaluated 79 gastric lesions histopathologically diagnosed as adenocarcinomas from the specimens obtained via endoscopic submucosal dissection. A DL was observed by Laser-BLI and LED-BLI in 98.7% (78/79) and 96.2% (76/79) of EGCs, respectively. The MVP observed using Laser-BLI and LED-BLI was irregular in 92.4% (73/79) and 89.9% (71/79), respectively. The MSP observed using Laser-BLI and LED-BLI was irregular in 83.5% (66/79) and 82.2% (65/79), respectively. According to the VSCS, diagnosable cancers were found in 94.9% (75/79) and 93.7% (74/79) of cases when using Laser-BLI and LED-BLI, respectively (p = 0.73; difference ratio, 1.2%; 95% CI -8.5 to 6.0%). CONCLUSIONS: LED-BLI could accurately visualize the DL, MVP, and MSP of EGCs and was not inferior to Laser-BLI. Therefore, LED-BLI can be used to diagnose EGC accurately according to the VSCS-based diagnosis criteria.

Diagnostic performance of magnifying blue laser imaging versus magnifying narrow-band imaging for identifying the depth of invasion of superficial esophageal squamous cell carcinoma.

Identifying the depth of invasion (DOI) of superficial esophageal squamous cell carcinoma (SESCC) is crucial to determine the indication for endoscopic resection. This retrospective, single-center study aimed to evaluate the diagnostic efficacy of magnifying blue laser imaging (M-BLI) compared with white-light imaging (WLI) or magnifying narrow-band imaging (M-NBI) for identifying the DOI of SESCC. A total of 160 consecutive patients with SESCCs who underwent endoscopic submucosal dissection were enrolled in this study. Still images of the lesion were obtained using WLI, M-BLI and M-NBI prior to endoscopic submucosal dissection. Three endoscopists retrospectively evaluated the DOI using WLI according to non-magnifying findings and using M-BLI and M-NBI images according to the magnifying endoscopic classification of the Japan Esophageal Society. The diagnostic accuracy of each modality was compared using the chi-square test. The DOIs in 160 SESCCs evaluated pathologically were as follows: invasion to the epithelium or lamina propria mucosa in 130, invasion to the lamina muscularis mucosa or submucosa to a depth ≤ 200 µm in 18, and invasion to the submucosa to a depth > 200 µm in 12. The overall diagnostic accuracy rates of WLI, M-BLI, M-NBI, WLI with M-BLI (WLI + M-BLI), and WLI with M-NBI (WLI + M-NBI) were 86.9, 91.2, 90.6, 95.6 and 94.4%, respectively. Significant differences were found between WLI and WLI + M-BLI or WLI + M-NBI (P = 0.006 and P = 0.021, respectively). The concordance of intrapapillary capillary loops between M-BLI and M-NBI was 91.2%. The kappa coefficients for interobserver variability of the three endoscopists for M-BLI and M-NBI were 0.728/0.649/0.792 and 0.729/0.666/0.791, respectively, while those for intraobserver variability were 0.919/0.746/0.778 and 0.736/0.720/0.745, respectively. Similar to M-NBI, M-BLI was useful in predicting the DOI of SESCCs.

Can image-enhanced endoscopy improve the diagnosis of Kyoto classification of gastritis in the clinical setting?

Endoscopic diagnosis of Helicobacter pylori (H. pylori) infection, the most common cause of gastric cancer, is very important to clarify high-risk patients of gastric cancer for reducing morbidity and mortality of gastric cancer. Recently, the Kyoto classification of gastritis was developed based on the endoscopic characteristics of H. pylori infection-associated gastritis for clarifying H. pylori infection status and evaluating risk factors of gastric cancer. Recently, magnifying endoscopy with narrow-band imaging (NBI) has reported benefits of the accuracy and reproducibility of endoscopic diagnosis for H. pylori-related premalignant lesions. In addition to NBI, various types of image-enhanced endoscopies (IEEs) are available including autofluorescence imaging, blue laser imaging, and linked color imaging. This review focuses on understanding the clinical applications and the corresponding evidences shown to improve the diagnosis of gastritis based on Kyoto classification using currently available advanced technologies of IEEs.

Efficacy and safety of endoscopic submucosal dissection using a scissors-type knife with prophylactic over-the-scope clip closure for superficial non-ampullary duodenal epithelial tumors.

BACKGROUND AND STUDY AIM: This study aimed to assess the safety and feasibility of endoscopic submucosal dissection (ESD) using a scissors-type knife with prophylactic closure using over-the-scope clip (OTSC) for superficial non-ampullary duodenal epithelial tumors (SNADETs). PATIENTS AND METHODS: Consecutive patients who underwent ESD for SNADETs >10 mm between January 2009 and July 2019 were retrospectively enrolled. We performed ESD using either a needle-type knife (Flush Knife-ESD) or a scissors-type knife (Clutch Cutter-ESD). Mucosal defects were prophylactically closed using three methods: conventional clip, laparoscopic closure, or OTSC. RESULTS: A total of 84 lesions were resected using the Flush Knife-ESD and the Clutch Cutter-ESD (37 and 47 patients, respectively), and conventional clip, laparoscopic closure, and OTSC for mucosal defect closure after ESD were applied in 13, 13, and 56 lesions, respectively. The R0 resection rate was significantly higher in the Clutch Cutter-ESD than that in the Flush Knife-ESD (97.9% vs 83.8%, respectively, P = 0.040). The intraoperative perforation rate was significantly lower in the Clutch Cutter-ESD than in the Flush Knife-ESD (0% vs 13.5%, respectively, P = 0.014). Complete closure rates of conventional clip, laparoscopic closure, and OTSC were 76.9%, 92.3%, and 98.2%, respectively (P = 0.021); and delayed perforation rates were 15.4%, 7.7%, and 1.8%, respectively (P = 0.092). CONCLUSIONS: Endoscopic submucosal dissection using a scissors-type knife with prophylactic OTSC closure is safe and feasible for the low-invasive treatment of SNADETs.

Efficacy of Clutch Cutter for Standardizing Endoscopic Submucosal Dissection for Early Gastric Cancer: A Propensity Score-Matched Analysis.

BACKGROUND/AIMS: The purpose of this study was to evaluate the safety and efficacy of gastric endoscopic submucosal dissection (ESD) using the Clutch Cutter (CC), a scissor-type knife, compared with those of procedures using conventional devices. METHODS: This single-center retrospective study evaluated 237 patients with early gastric cancer: 83 who underwent ESD using the CC group and 154 who underwent ESD using the insulated-tip knife 2 (IT2 group). Clinicopathological features and technical outcomes were compared between the 2 groups using a propensity score-matched analysis. RESULTS: In 61 pairs of matched patients, there was no significant difference in R0 resection, perforation, or postoperative bleeding between the CC and IT2 groups. Comparisons between the 2 groups showed similar treatment outcomes for an expert endoscopist. Nevertheless, there were significant differences between the 2 groups for nonexperts in terms of self-completion (61.7 and 24.5%, respectively, p < 0.001), mean procedure times (45 and 61 min, respectively, p = 0.002), and mean numbers of intraoperative bleeding points and bleeding points requiring hemostatic forceps (3 and 0 vs. 8 and 3, respectively, p < 0.001). CONCLUSION: Better self-completion rates and shorter procedure times were noted for gastric ESD using the CC by nonexperts than for that using IT2, probably due to hemostatic efficacy.

Blue Laser Imaging-Bright Improves Endoscopic Recognition of Superficial Esophageal Squamous Cell Carcinoma.

Background/Aims. The aim of this study was to evaluate the endoscopic recognition of esophageal squamous cell carcinoma (ESCC) using four different methods (Olympus white light imaging (O-WLI), Fujifilm white light imaging (F-WLI), narrow band imaging (NBI), and blue laser imaging- (BLI-) bright). Methods. We retrospectively analyzed 25 superficial ESCCs that had been examined using the four different methods. Subjective evaluation was provided by three endoscopists as a ranking score (RS) of each image based on the ease of detection of the cancerous area. For the objective evaluation we calculated the color difference scores (CDS) between the cancerous and noncancerous areas with each of the four methods. Results. There was no difference between the mean RS of O-WLI and F-WLI. The mean RS of NBI was significantly higher than that of O-WLI and that of BLI-bright was significantly higher than that of F-WLI. Moreover, the mean RS of BLI-bright was significantly higher than that of NBI. Furthermore, in the objective evaluation, the mean CDS of BLI-bright was significantly higher than that of O-WLI, F-WLI, and NBI. Conclusion. The recognition of superficial ESCC using BLI-bright was more efficacious than the other methods tested both subjectively and objectively.

New-generation narrow band imaging improves visibility of polyps: a colonoscopy video evaluation study.

BACKGROUND: The benefits of narrow band imaging (NBI) in colorectal polyp detection remain questionable. Previous NBI has poorer brightness and resolution than white light (WL). However, recently these factors were improved by the new-generation video processor system (EVIS LUCERA ELITE) in comparison with the previous system (EVIS LUCERA SPECTRUM). The aim of this study was to investigate whether NBI with EVIS LUCERA ELITE could improve the visibility of colorectal polyps compared to WL. METHODS: We analyzed prospectively 240 colorectal polyps (group 1: ELITE with CF-HQ290 scope, 80 polyps; group 2: ELITE with PCF-Q260AZI scope, 80 polyps; group 3: SPECTRUM with PCF-Q260AZI scope, 80 polyps) whose videos were recorded using NBI and WL at Kyoto Prefectural University of Medicine. The videos were evaluated in a randomized order by three experts and three non-experts. Each polyp was assigned a polyp visibility score from 4 (excellent visibility) to 1 (poor visibility). The polyp visibility scores in each mode and their relationship to the clinical characteristics were analyzed. RESULTS: The mean polyp visibility scores of NBI with ELITE system were significantly higher than those of WL (ELITE with CF-HQ290: 3.14 ± 0.87 vs. 2.75 ± 0.98, p < 0.0001, ELITE with PCF-Q260AZI: 3.03 ± 0.92 vs. 2.83 ± 0.93, p = 0.0006). Conversely, the mean polyp visibility score of NBI using SPECTRUM system with PCF-Q260AZI was significantly lower than WL (2.75 ± 1.06 vs. 3.05 ± 0.92, p < 0.0001). CONCLUSIONS: Our study showed that NBI using EVIS LUCERA ELITE improved polyp visibility.