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

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

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

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

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

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

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

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

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

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

What's New with Endoscopic Treatments for Early Gastric Cancer in the "Post-ESD Era"?

BACKGROUND: Endoscopic treatments for gastric cancers have still been progressing even after the great success of endoscopic submucosal dissection (ESD). SUMMARY: In further advancements of ESD, safe and less-invasive procedures are challenged by managing postoperative bleeding, one of the major adverse events in ESD. Covering the mucosal defect after removal of lesions appears reasonable and effective for preventing delayed bleeding from the post-ESD ulcers. Shielding with biodegradable sheets is attempted on clinical trials, which show equivocal results. Although suturing of the mucosal rims is technically challenging, pilot studies demonstrate favorable outcomes for avoiding post-ESD bleeding even in cases at high risk. In cases after noncurative resection of ESD, the selection of patients who truly require additional gastrectomy with lymph node dissection is important to provide necessary surgery. Risk stratification of lymph node metastases and surgery has been developed, which offers tailor-made management to each patient considering the risks and benefits. In surgery, function-preserving gastrectomy to minimize the resection area in both lymphadenectomy and the primary site is clinically introduced. The sentinel node navigation surgery is promising to realize the minimally invasive gastrectomy, and it should strongly fit ESD as well as laparoscopic endoscopic cooperative surgery or endoscopic full-thickness resection, although nonexposure approaches are desirable. Key Message: Development for less-invasive managements on gastric cancer will be continued in step with the advancement of endoscopic treatments.

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

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

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

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

Endoscopic hand suturing for mucosal defect closure after gastric endoscopic submucosal dissection may reduce the risk of postoperative bleeding in patients receiving antithrombotic therapy.

OBJECTIVES: Endoscopic hand suturing (EHS) is expected to decrease the risk of post-endoscopic submucosal dissection (ESD) bleeding by closing mucosal defects. We investigated the efficacy of EHS after gastric ESD in patients with antithrombotic agents. METHODS: In this prospective single-arm trial, patients taking antithrombotic agents for cardiovascular disease, arrhythmia, cerebrovascular disease and/or peripheral arterial disease and having <3-cm gastric neoplasms were recruited. The mucosal defects after ESD were closed by EHS in which the needle was delivered through an overtube, and the mucosal rim of the defect was continuously sutured in a linear fashion by manipulating the needle grasped with the needle holder, followed by cutting the remnant suture and retrieval of the needle. The primary endpoint was the incidence of postoperative bleeding within 4 weeks after ESD. RESULTS: Twenty-two lesions in 20 patients (continuing antiplatelet agents in 11, anticoagulant agents in eight, both in one) underwent ESD followed by EHS. All defects (median size, 30 mm; range, 12-51 mm) were completely closed by EHS and remained closed on postoperative day 3. The median number of stitches was six (range, 4-8) and median suturing time was 36 (range, 24-60) min. There were no adverse events during/after EHS or postoperative bleeding. CONCLUSIONS: Postoperative bleeding was not observed in patients taking antithrombotic agents without perioperative cessation. EHS appears to be useful for prevention of post-gastric ESD bleeding in high-risk patients. (Clinical registration number: UMIN000024184).

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

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

Three-dimensional flexible endoscopy enables more accurate endoscopic recognition and endoscopic submucosal dissection marking for superficial gastric neoplasia: a pilot study to compare two- and three-dimensional imaging.

BACKGROUND: Three-dimensional (3D) visualization offers better depth recognition than two-dimensional (2D) imaging, thus helping to provide more useful information. We compared 3D and 2D endoscopy with regard to endoscopic recognition and endoscopic submucosal dissection (ESD) marking for superficial gastric neoplasia. METHODS: ESD marking was performed on half of a neoplasia margin under 2D observation and the on other half under 3D observation for 28 gastric lesions (26 early gastric cancers and 2 adenomas). The accuracy of ESD marking was evaluated based on the distance between the pathological and endoscopic neoplasia margins measured on histology sections of ESD specimens. The technical ease of ESD marking and endoscopic lesion recognition (lesion morphology, lesion extent, and comprehensive endoscopic cognition) were assessed using visual analog scale (VAS) questionnaires. RESULTS: The mean distance between the pathological and endoscopic margins under 3D observation (1.03 ± 0.80 mm) was significantly (p = 0.002) shorter than that under 2D observation (1.94 ± 1.96 mm). The VAS for technical ease of ESD marking under 3D observation was significantly better (p < 0.01) than that under 2D observation. The VAS for all aspects of endoscopic recognition under 3D observation was significantly better (p < 0.01) than under 2D observation. CONCLUSIONS: 3D flexible endoscopy achieved more accurate endoscopic recognition and ESD marking for superficial gastric neoplasia than a 2D approach in a clinical setting of ESD.

Differences in clinical characteristics between conservative-treatment-response group and refractory (surgical-treatment) group in patients with jackhammer esophagus.

BACKGROUND: Jackhammer esophagus (JE) is a rare disease with unclear clinical features. The objective of this study was to retrospectively compare the clinical characteristics of patients with JE whose symptoms were controlled with conservative treatment, such as observation or medication, versus those who were required surgical treatment, such as surgical myotomy or per oral endoscopic myotomy. METHODS: Eighteen patients with JE were included in this study. The patients were divided into two groups: patients who responded to conservative treatment (C group) and patients who were refractory to conservative treatment and underwent surgery (S group). Patient age, sex, disease duration before treatment, symptoms, esophagogastroduodenoscopic (EGD) findings, esophagographic findings, esophageal wall thickness on computed tomography, number of swallows with hypercontractile peristalsis in 10 water swallows, and maximum distal contractile integral (DCI) were compared between the groups. RESULTS: Thirteen of 18 patients (72%) were in the C group and five of 18 (28%) were in the S group. There were no significant differences in age, sex, disease duration before treatment, symptoms, EGD findings, esophagographic findings, esophageal wall thickness, or number of swallows with hypercontractile peristalsis between the groups. On Starlet high-resolution manometry, the median maximum DCI value was significantly higher in the S group (32,651 mmHg-s-cm) than in the C group (17,926 mmHg-s-cm) (P = 0.0136). CONCLUSIONS: JE treatment should be carefully considered because some patients require surgery, whereas others are controlled with conservative treatment alone. A higher DCI value in patients with JE may predict resistance to conservative treatment.

Endoscopic hand-suturing is feasible, safe, and may reduce bleeding risk after gastric endoscopic submucosal dissection: a multicenter pilot study (with video).

BACKGROUND AND AIMS: Endoscopic hand-suturing (EHS) provides secure intraluminal mucosal closure and should decrease the risk of adverse events after gastric endoscopic submucosal dissection (ESD). We prospectively investigated the feasibility and safety of EHS after gastric ESD, particularly for preventing post-ESD bleeding. METHODS: Patients scheduled for gastric ESD at 3 institutions were prospectively recruited. Just after ESD, the mucosal defect was closed by EHS. The primary outcome was endoscopic assessment of adequately sustained closure of the defect on postoperative day 3. Endoscopy was performed to assess maintenance of the closure for the primary outcome. During postoperative weeks 3 to 4, patients were interviewed as outpatients about any occurrence of delayed bleeding. RESULTS: Data from 30 patients (15 each who did or did not take antithrombotic agents) were analyzed. Mucosal closure by EHS was completed in 29 of 30 cases (97%) and was well maintained on postoperative day 3 in 25 cases (84%). Emergency endoscopy was required for major postoperative bleeding in 3 cases (10%), including 1 in which suturing had been incomplete. Excluding 1 patient with a remnant stomach, the other 24 with sustained closure had no bleeding, regardless of whether they did or did not take antithrombotic agents (0/11 and 0/13, respectively). No serious adverse events occurred during EHS. CONCLUSIONS: Results show that EHS is feasible and safe with favorable outcomes. Provided that mucosal suturing is successfully completed and sustained, post-ESD bleeding can be decreased even in patients undergoing antithrombotic therapy. (Clinical trial registration number: UMIN 000033988.).

Efficacy of a new image-enhancement technique for achieving hemostasis in endoscopic submucosal dissection.

BACKGROUND AND AIMS: Hemostasis during endoscopic submucosal dissection (ESD) can sometimes be challenging and stressful for the endoscopist. Therefore, we aimed to assess the usefulness of dual red imaging (DRI), a new image enhancement technique that uses 3 wavelengths (540, 600, and 630 nm) to visualize bleeding points and to examine the efficacy of DRI in shortening the time required to achieve hemostasis (hemostasis time) during ESD. METHODS: DRI and white-light imaging (WLI) were used alternately for managing 378 bleeding events in 97 patients undergoing ESD. Hemostasis time for each hemostasis event was measured. Using portable eye-tracking glasses, 4 experienced endoscopists were shown random videos of intraoperative bleeding during ESD (20 cases each on WLI and DRI) and identified the bleeding point in each video. The mean distances of eye movement per unit of time until the bleeding point were identified in each video and compared between the WLI and DRI groups. RESULTS: Average hemostasis time was significantly shorter in the DRI group. The mean distance of eye movement was significantly shorter in the DRI group than in the WLI group for all endoscopists. CONCLUSIONS: DRI can offer useful images to help in clearly detecting bleeding points and in facilitating hemostasis during ESD. It is feasible and may help in successfully performing ESD that is safer and faster than WLI. (Clinical trial registration number: UMIN000018309.).

Endoscopic suturing promotes healing of mucosal defects after gastric endoscopic submucosal dissection: endoscopic and histologic analyses in in vivo porcine models (with video).

BACKGROUND AND AIMS: Endoscopic suturing of mucosal defects after endoscopic submucosal dissection (ESD) is expected to prevent postoperative adverse events. We aimed to endoscopically and histologically evaluate the healing process of post-ESD mucosal defects closed with endoscopic hand suturing (EHS) in in vivo porcine models. METHODS: Twelve mucosal defects (2 cm in size) were created in 2 pigs (6 defects per pig). Initially, 2 defects were created: one was closed with EHS (sutured group) and the other was kept open (control group). On postoperative days (PODs) 7 and 14, 2 additional defects were created in each session, and they were treated in the same manner as in the initial procedure. On POD 21, the entire stomach, with the 6 lesion sites, was extracted for histologic evaluation after endoscopic observation. RESULTS: Endoscopically, all sutured sites remained closed in all sessions (PODs 7, 14, and 21). Histologically, on POD 14, the epithelium and muscularis mucosae were appropriately connected. The mucosae were covered with the epithelium without inversion of the mucosal edge in the sutured group, whereas the ulcer bed was exposed in the control group. Furthermore, the degree of neovascularity and fibroblasts in the submucosa was smaller in the sutured group than that in the control group. CONCLUSIONS: Our findings suggest that endoscopic suturing promotes healing of post-ESD mucosal defects histologically in in vivo porcine models. Thus, endoscopic mucosal closure after ESD might be clinically useful for the prevention of delayed perforation/bleeding if secure suturing is performed endoscopically.

A novel endoscopic hand-suturing technique for defect closure after colorectal endoscopic submucosal dissection: a pilot study.

BACKGROUND: This study aimed to demonstrate the feasibility of endoscopic hand-suturing (EHS) and attainability of sustained closure after colorectal endoscopic submucosal dissection (ESD). METHODS: EHS was defined as uninterrupted endoscopic suturing of the mucosal defect after colorectal ESD using an absorbable barbed suture and a through-the-scope needle holder. Following individual EHS training using an ex vivo porcine colonic model, two experienced endoscopists performed EHS. Repeat colonoscopy was performed on the third or fourth day after ESD to examine the EHS site. The primary end point was the complete EHS closure rate, and secondary end points were sustained closure and post-ESD bleeding rates. RESULTS: 11 lesions were included. Median size of the mucosal defect was 38 mm (range 25 - 55 mm) and the lesion characteristics were as follows: lower rectum/upper rectum/ascending colon/cecum = 3/3/2/3, and 0-IIa/0-Is + IIa/others = 5/4/2. EHS was not attempted in two patients owing to difficulty in colonoscope reinsertion after ESD and intraoperative perforation, respectively. EHS was performed for nine lesions, and the complete EHS closure rate was 73 %. Median procedure time for suturing was 56 minutes (range 30 - 120 minutes) and median number of stitches was 8 (range 6 - 12). Sustained closure and post-ESD bleeding rates were 64 % and 9 %, respectively. CONCLUSIONS: EHS achieved complete and sustained closure in the colorectum. However, EHS is not currently clinically applicable given the long procedure time. Further modifications of the technique and devices are desirable.

Clinical outcomes of non-exposed endoscopic wall-inversion surgery for gastric submucosal tumors: long-term follow-up and functional results.

BACKGROUND AND AIMS: To avoid the risk of iatrogenic dissemination during procedures, we have developed a combined laparoscopic and endoscopic surgery with a nonexposure technique for resection of gastric tumors. The study aim was to evaluate the feasibility and safety of non-exposed endoscopic wall-inversion surgery (NEWS) for gastric submucosal tumors (SMTs). METHODS: Between August 2013 and February 2018, NEWS was performed for 42 patients with gastric SMTs ≤ 3 cm in diameter at our institution. We retrospectively investigated the patients' backgrounds, operative and perioperative outcomes, tumor pathological characteristics, and follow-up data. RESULTS: All tumors were resected with negative margins by NEWS. The median operation time was 198 min, and the median estimated blood loss was 5.0 mL. Adverse events occurred in one patient with pneumonia. All patients were alive without recurrence within the median follow-up period of 29.2 months. The average body weight loss rate was 0.3 ± 4.0%. No food residue was observed at endoscopic follow-up. CONCLUSIONS: On the basis of slight body weight loss and the absence of food residue observed in the postoperative endoscopy, NEWS appeared to be safe and feasible for gastric SMTs and to preserve function of the remnant stomach.

Usefulness of the flexible traction method in gastric endoscopic submucosal dissection: an in-vivo animal study.

BACKGROUND: An appropriate traction of the target lesion is a key for a safe and secure ESD procedure. We proposed the flexible traction method (F-trac) which provided an optimal traction using an endoscopic hand-suturing (EHS) and investigated the usefulness of this technique for gastric ESD in-vivo porcine model. METHODS: In the F-trac method, a lesion was suspended by pulling proximal side of endoscope which was connected to the contralateral side with a barbed suture using the EHS technique just before starting the submucosal dissection. A single endoscopist performed conventional ESD (C-ESD) and F-trac ESD alternately for a total of ten simulating lesions of 3 cm in diameter in a live porcine stomach. The pig was rotated so that each lesion was positioned in the direction of the gravity. The procedure time, technical accuracy, adverse events, and the number of additional injection to the submucosal layer during dissection were evaluated. RESULTS: The total ESD procedure time in the F-trac group was significantly shorter than in C-ESD group (19.0 min vs. 30.6 min, p = 0.039). There were no significant differences between both groups in muscular layer damage, sample damage, perforation, and intraoperative bleeding. The number of additional injection in the F-trac group was significantly fewer than that in C-ESD group (0 times vs. 4.4 times, p = 0.027). CONCLUSIONS: In gastric ESD, F-trac might be useful for shortening the total procedure time. This method can facilitate optimal traction without disturbing the endoscopic visualization and the movement of endoscope.

Feasibility of endoscopic submucosal dissection for colorectal neoplasia at anastomotic sites: a retrospective study.

BACKGROUND: Metachronous colorectal lesions sometimes occur at anastomotic sites following colorectal surgery, which increases the risk of developing colorectal cancer. However, these lesions are difficult to treat even with minimally invasive methods such as endoscopic submucosal dissection (ESD). Thus, we aimed to evaluate the outcomes of ESD for colorectal lesions at anastomotic sites following colorectal surgery. METHODS: We retrospectively investigated 11 patients with post-surgical colorectal lesions at anastomotic sites who later underwent ESD from May 2010 to April 2019 at Keio University Hospital, Tokyo, Japan. We examined the patients' background (tumor location, macroscopic type, tumor size, histological type, and depth of invasion) and treatment outcomes (procedure duration, en bloc resection rate, R0 resection rate, and adverse events). RESULTS: The patients' mean age was 66 years. There were two lesions in the transverse colon, six in the rectum, one in the anal canal, and two in the ileal pouch. The median tumor size was 25 mm. The macroscopic types were the protruded type (1 lesion) and the flat or depressed type (10 lesions). The pathological diagnoses were adenoma (4 lesions), intramucosal cancer (corresponding to high-grade dysplasia) (6 lesions), and muscularis propria cancer (1 lesion). The median procedure duration was 50 min; en bloc resection rate was 88.9% and R0 resection rate was 66.7%. The only adverse event was delayed post-ESD bleeding. CONCLUSIONS: A high en bloc resection rate without perforation was achieved with ESD for lesions at anastomotic sites. Although ESD for lesions at anastomotic sites is a technically challenging procedure because of severe submucosal fibrosis, this approach could prevent the need for repeated surgical resection.

Epidemiology of colonic diverticula and recent advances in the management of colonic diverticular bleeding.

There is the East-West paradox in prevalence and phenotype of colonic diverticula, but colonic diverticular bleeding (CDB) is the most common cause of acute lower gastrointestinal bleeding worldwide. Death from CDB can occur in elderly patients with multiple comorbidities, thus the management of CDB is clinically pivotal amid the aging populations in the East and West. Colonoscopy is the key modality for managing the condition appropriately; however, conventional endoscopic hemostasis by thermal coagulation and clipping cannot achieve the expected results of preventing early rebleeding and conversion to intensive intervention by surgery or transcatheter arterial embolization. Ligation therapy by endoscopic band ligation or endoscopic detachable snare ligation has emerged recently to enable more effective hemostasis for CDB, with an early rebleeding rate of approximately 10% and very rare conversion to intensive intervention. Ligation therapy might in turn reduce long-term rebleeding rates by eliminating the target diverticulum itself. Adverse events have been reported with ligation therapy including diverticulitis of the ascending colon in less than 1% of cases and perforation of the sigmoid colon in a few cases, thus more data are necessary to verify the safety of ligation therapy. Endoscopic hemostasis is indicated only for diverticulum with stigmata of recent hemorrhage (SRH), but the detection rates of SRH are relatively low. Therefore, efforts to increase detection are also key for improving CDB management. Urgent colonoscopy and triage by early contrast-enhanced computed tomography may be candidates to increase detection but further data are necessary in order to make a conclusion.