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

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

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

Prevention of postoperative anastomotic leakage in rectal surgery is still required. This study investigated the feasibility of endoscopic hand suturing (EHS) on rectal anastomosis ex vivo. By using isolated porcine colon, we prepared ten anastomoses 6–10 cm from the virtual anus. Then, we sutured anastomoses intraluminally by EHS, which involved a continuous suturing method in 5 cases and a nodule suturing method with extra corporeal ligation in 5 cases. Completeness of suturing, number of stitches, procedure time and presence of stenosis were investigated. Furthermore, the degree of stenosis was compared between the two suturing methods. In all cases, EHS were successfully completed. The median number of stitches and procedure time was 8 and 5.8 min, respectively. Stenosis was created in all continuous suturing cases whereas none was seen in nodule suturing cases. The shortening rate was significantly greater in the continuous suturing method than in the nodule suturing method. Intraluminal reinforcement of rectal anastomosis by EHS using nodule suturing with extra corporeal ligation is feasible without stenosis, which may be helpful as a countermeasure against possible postoperative anastomotic leakage in rectal surgery.