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).

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.

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.

How I do it: Endoscopic diagnosis for superficial non-ampullary duodenal epithelial tumors.

There are no reports on detailed endoscopic diagnosis of superficial non-ampullary duodenal epithelial tumors (SNADET) except for relatively small case series. Herein, we conducted a prospective observational study to investigate the relationship between endoscopic findings and histopathological diagnosis of SNADET. A total of 163 SNADET diagnosed using magnified endoscopic examination with image-enhanced endoscopy (IEE-ME) were prospectively registered in this study. We investigated location, size, macroscopic type, color, and IEE-ME findings including surface structure (closed- or open-loop) and presence of white opaque substance (WOS) in SNADET. We analyzed association between these findings and histopathological diagnosis of SNADET based on the Vienna classification (VCL) using logistic regression analysis. In univariate analysis, lesion size, superficial structure, and WOS deposition showed statistical significance, and the oral side of the lesion location showed statistical tendency for association with VCL C4/5. In multivariate analysis, lesion size (odds ratio [OR], 2.92; 95% CI, 1.94-4.39; P < 0.05) and negative WOS (OR, 5.59; 95% CI, 1.72-18.1; P < 0.05) were significantly associated with VCL C4/5 lesions. Superficial structures with a closed-loop pattern on the surface showed statistical tendency for predicting VCL C4/5 lesions (OR, 2.15; 95% CI, 0.86-5.37; P = 0.10). Based on these findings, we concluded that negative WOS by IEE-ME and lesion size were independent predictors of VCL C4/5 SNADET. These factors may help us to understand of pathophysiology of SNADET and to select appropriate therapeutic strategies.

Feasibility study comparing underwater endoscopic mucosal resection and conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumor < 20 mm.

BACKGROUND AND AIM: Underwater endoscopic mucosal resection (UEMR) has been reported as an alternative to conventional EMR for superficial non-ampullary duodenal epithelial tumors (SNADET). However, the detailed outcomes are unclear. This study aimed to compare the clinical outcomes between UEMR and EMR for SNADET <20 mm. PATIENTS AND METHODS: This is a retrospective observational study using a prospective maintained database. From November 2017 to December 2018, 104 consecutive cases of attempted UEMR for SNADET <20 mm were prospectively allocated. A total of 240 cases of attempted EMR were chosen as historical controls. We compared technical success rate, defined as the resection rate without conversion to ESD; en bloc resection rate; R0 resection rate; and adverse event rate. Next, multivariate analyses were constructed to identify predictors of conversion to ESD, piecemeal resection, and RX or R1 (RX/R1) resection. RESULTS: Technical success rate of UEMR was significantly higher than that of EMR (87% and 70%, P < 0.01). En bloc resection and R0 resection rates of UEMR were significantly lower than those of EMR (en bloc resection: 87% vs 96%, P < 0.01; R0 resection: 67% vs 80%, P = 0.05). Concerning adverse events, there were no significant differences. In multivariate analyses, attempted EMR, lesion size and depressed type were independent predictors of conversion to ESD. Attempted UEMR was an independent predictor of piecemeal resection and RX/R1 resection. CONCLUSION: The present study indicated that UEMR could be a feasible endoscopic resection method for SNADET (UMIN000025442).

Clinical impact of closure of the mucosal defect after duodenal endoscopic submucosal dissection.

BACKGROUND AND AIMS: Delayed adverse events (bleeding or perforation) are major concerns associated with duodenal endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy of prophylactic closure of the mucosal defect after duodenal ESD. METHODS: This is a retrospective study from a university hospital. One hundred sixty-eight patients (173 lesions) who underwent duodenal ESD between July 2010 and June 2017 were included in this study. The study participants were divided into 3 subgroups according to the degree of closure: complete group, incomplete group, and unclosed group. The proportion of delayed adverse events, maximum serum level of C-reactive protein (CRP), and total length of hospital stay were compared among these subgroups. Moreover, a multivariate logistic regression model was constructed to identify the risk factors for delayed adverse events. RESULTS: The proportion of delayed adverse events in the complete group, incomplete group, and unclosed group were 1.7%, 25%, and 15.6%, respectively. The difference between the complete group and the other groups was significant (P < .01). The maximum serum CRP level was much lower (1.51 ± 2.18 mg/dL vs 6.28 ± 10.0 mg/dL, P < .01), and the length of hospital stay was significantly shorter in the complete group than in the incomplete/unclosed group (median [range] 5 [5-14] days vs 8 [4-59] days, P < .01). Multivariate analysis revealed that complete closure had a significant decrease in delayed adverse events (odds ratio [OR], 0.055; 95% confidence interval [CI], 0.01-0.29; P < .01), and a lesion located distal from the descending part showed a statistical tendency to an increase in delayed adverse events (OR, 4.48; 95% CI, 0.85-23.6; P = .08). CONCLUSION: The present study revealed that complete closure of the mucosal defect after duodenal ESD significantly decreased the number of delayed adverse events and improved other outcomes.

Current Status and Challenges of Endoscopic Treatments for Duodenal Tumors.

BACKGROUND: Superficial tumors of the duodenum, other than ampullary tumors, have been traditionally considered rare. However, reports of this kind of tumor have increased in recent times, and the demand for minimally invasive treatments have also increasing. SUMMARY: Adenomas and intramucosal carcinomas are target lesions for treatment. A preoperative diagnosis has not been established, but unnecessary biopsies increase the difficulty of treatment and should be avoided. Cold snare polypectomy, endoscopic mucosal resection (EMR), and underwater EMR are treatment options for small lesions. Endoscopic submucosal dissection enables secure resection even for large lesions, but it is technically demanding and associated with a higher complication rate. After endoscopic resections, exposure of digestive juices is believed to cause delayed complications. To prevent these complications, several closing and covering methods are proposed, with favorable clinical results. Key message: A treatment method should be chosen based on each patient's situation. With any of the treatment methods, post-resection measures are required to prevent delayed complications. Secure closure of resection wounds seems promising.

Effects of EUS-guided intratumoral injection of oligonucleotide STNM01 on tumor growth, histology, and overall survival in patients with unresectable pancreatic cancer.

BACKGROUND AND AIMS: Carbohydrate sulfotransferase 15 (CHST15) promotes tumor growth and invasion and is considered to be an emergent therapeutic target for pancreatic cancer. The aim of this study was to evaluate the safety and efficacy of EUS-guided fine-needle injection (EUS-FNI) of STNM01, the double-stranded RNA oligonucleotide that specifically represses CHST15, for use in patients with pancreatic cancer. METHODS: Six patients with unresectable pancreatic cancer, treated at Tokyo Metropolitan Geriatric Hospital, were used in this open-labeled, investigator-initiated trial. A total of 16 mL STNM01 (250 nM) was injected into the tumor through EUS-FNI. The study's primary endpoint was safety, with a secondary endpoint of tumor response 4 weeks after the initial injection. Some patients received a series of infusions as extensions. The local expression of CHST15 and overall survival (OS) were also evaluated. RESULTS: There were no adverse events. The mean tumor diameter changed from 30.7 to 29.3 mm 4 weeks after injection. Four patients exhibited necrosis of tumor in biopsy specimens. CHST15 was highly expressed at baseline, with 2 patients showing large reductions of CHST15 at week 4. The mean OS of these 2 patients was 15 months, whereas it was 5.7 months for the other 4 patients. CONCLUSIONS: EUS-FNI of STNM01 in pancreatic cancer is safe and feasible. The CHST15 reduction could predict tumor progression and OS. Injections of STNM01 during the beginning of treatment may reduce CHST15 and warrants further investigation.

Endoscopic string clip suturing method: a prospective pilot study (with video).

BACKGROUND AND AIMS: We developed a suturing method with string and clips for a single-channel endoscope. The feasibility of the string clip suturing method is evaluated in this prospective pilot study. METHODS: This study involved 10 consecutive patients who underwent endoscopic submucosal dissection (ESD) for a duodenal tumor. Polyester string was tied to the arm of a partially out thrust clip. The clip and string can be passed through the instrument channel (3.2 mm) of a single-channel endoscope. The clip with string was placed at the distal edge of the large mucosal defect. A second clip was hooked on the string and placed on the opposite side. Both clips were gathered by pulling the free end of the string, and additional clips were placed to achieve complete closure. This method was compared with that for the previous 10 patients without mucosal closure after duodenal ESD. RESULTS: Mean size of resected specimens was 39.1 ± 12.4 mm. The success rate of the string clip suturing method was 100% (10/10). The mean procedure time was 23.4 ± 13.8 minutes. Perforation during ESD occurred in 1 patient and was successfully closed by this method. None of the treated patients developed serious adverse events after the procedure. Compared with the no-suture group, the length of stay was significantly shorter (P = .038). CONCLUSION: The string clip suturing method appears to be a safe and effective method for closure of large mucosal defects. (Clinical trial registration number: UMIN000023698.).

Outcomes of endoscopic resection for superficial duodenal epithelial neoplasia.

BACKGROUND AND AIMS: Pancreaticoduodenectomy is an invasive procedure, and endoscopic resection (ER) is an alternative therapy. However, details regarding the outcomes of ER are unknown, especially for superficial duodenal epithelial neoplasia (SDET). The aim of this study was to elucidate the outcomes of ER for SDET and to compare EMR with endoscopic submucosal dissection (ESD). METHODS: This was a retrospective observational study. From June 2010 to June 2017, 320 cases of endoscopically resected SDET (146 EMR-treated cases and 174 ESD-treated cases) were included in this study. We analyzed the proportions of en bloc resection, R0 resection, perforation, and bleeding as outcomes of ER and compared outcomes between the EMR and ESD groups. Next, we collected data on the features and clinical course of cases with adverse events. RESULTS: The proportions of en bloc resection and R0 resection among all cases were 96.6% and 83.4%, respectively. In over 95% of cases, ESD achieved en bloc resection, regardless of lesion size. The incidences of perforation and bleeding were 8.8% and 3.4%, respectively, and the former was largely successfully managed by conservative treatment. The mortality rate was 0%, and all patients were discharged with a median hospital stay of 8.5 days (range, 4-52 days). Evaluation of the hospital stay duration according to lesion circumference revealed a significantly longer duration for lesions present on the medial wall than for other lesions (median 41 vs 7 days, P = .0331). CONCLUSION: The present study revealed that ER achieved secure en bloc resection, with the treatment type (ESD or EMR) selected according to the lesion size. A lesion located on the medial wall was associated with worse outcomes, such as prolonged hospital stay after perforation.

The role of colorectal endoscopic submucosal dissection in patients with ulcerative colitis.

BACKGROUND AND AIM: Patients with ulcerative colitis have an increased risk of colorectal dysplasia. Endoscopic submucosal dissection (ESD) for neoplastic lesions in ulcerative colitis remains controversial. The aim of this study was to clarify the role of ESD in the treatment strategy for ulcerative colitis. METHODS: We retrospectively investigated 25 patients with ulcerative colitis in clinical remission who underwent colorectal ESD at 2 referral centers. We analyzed short-term and long-term outcomes. Preoperative diagnoses based on biopsy or endoscopy were also compared with the histologic diagnoses of resected specimens. RESULTS: The mean size of the resected specimens was 34.9 ± 17.1 mm. The mean procedure time for ESD was 71.3 minutes. En bloc resection and R0 resection rates were achieved in 100% (25/25) and 76% (19/25), respectively. Postoperative bleeding and perforation during the procedure occurred in 0% and 4%, respectively. Five patients with noncurative resection underwent additional surgery. During a median 21 months (range, 8-80 months) follow-up, local recurrence did not occur. Metachronous high-grade dysplasia occurred in 1 case (4%). The biopsy predicted a final histologic diagnosis of carcinoma with a sensitivity of 72.2% (95% confidence interval [CI], 46.5-90.3), accuracy of 78.2% (95% CI, 56.3-92.5). The endoscopic findings predicted a final histologic diagnosis of carcinoma with a sensitivity of 72.2% (95% CI, 46.5-90.3), accuracy of 76% (95% CI, 54.9-90.6). CONCLUSION: ESD for neoplasms in ulcerative colitis is feasible by expert endoscopists and may avoid unnecessary surgery. Because the biopsy and endoscopic findings had relatively low accuracy for the final histology, ESD could have a curative as well as a diagnostic purpose.

Potential for peritoneal cancer cell seeding in endoscopic full-thickness resection for early gastric cancer.

BACKGROUND AND AIMS: During endoscopic full-thickness resection (EFTR) for cancers, whether exposure of the lumen to the abdominal cavity during the procedure is acceptable is controversial because of the potential risk of tumor cell seeding. To assess the possibility of transplantation as a result of contact with tumor cells during the procedure, we prospectively investigated the ability of cancer cells to be detached by touching the tumor surface. METHODS: In 48 patients with a single early gastric cancer resected by endoscopic submucosal dissection, stamp cytology was performed by touching the surface of the specimens to glass slides. Samples were obtained from cancerous and noncancerous areas, constituting the study and control groups, respectively. The detection rate of malignant class IV or V (C-IV/C-V) samples was investigated with Papanicolaou staining. The rate of CD44v9-positive cases, a cancer stem cell marker, was assessed in C-IV/C-V samples with immunohistochemical staining. RESULTS: Detection rates of C-IV/C-V samples in the cancerous group (53/192 slides, 27.6%) differed significantly from those of the C-IV/C-V samples in the noncancerous group (0/96 slides, 0%). Among the 53 slides of C-IV/C-V samples in the cancerous group, CD44v9 cells were expressed in 18 slides (34.0%). CONCLUSIONS: These data suggest that cancer cells, including cancer stem cells, in early gastric cancers are easily detached via contact with the tumor surface. In EFTR, a nonexposure approach is recommended to avoid the risk of iatrogenic cancer cell seeding via contact with and transplantation of cancer cells.

Rebamipide solution: a novel submucosal injection material to promote healing speed and healing quality of ulcers induced by endoscopic submucosal dissection.

BACKGROUND AND AIMS: Rebamipide is administered perorally to protect the gastric mucosa. We assessed the efficacy and safety of a novel rebamipide solution as a submucosal injection material for endoscopic submucosal dissection (ESD) using an in vivo porcine model. METHODS: An endoscopist blinded to the test agents performed ESDs of hypothetical 30 mm lesions using a 2% rebamipide solution at 2 sites (rebamipide group) and a saline solution at 2 other sites (control group) in the stomachs of 8 pigs. The technical outcomes were compared between the 2 groups. The gastric ulcer stages were evaluated by endoscopy once weekly for 4 weeks after the ESD to determine the healing score (1-6). The pigs were killed at 1 week (n = 2), 2 weeks (n = 2), and 4 weeks (n = 4) after the ESD for pathologic evaluation of ESD-induced ulcers and scarring. RESULTS: There were no significant differences in any of the technical outcomes between the 2 groups, and no adverse events related to the ESD in any of the animals. The healing score was significantly higher in the rebamipide group than in the control group at 2 weeks (P = .027), 3 weeks (P = .034), and 4 weeks (P = .012). In the histopathologic assessment, fibrosis was significantly less extensive in the rebamipide group than in the control group at 2 weeks (P = .02) and 4 weeks (P = .04). CONCLUSIONS: The rebamipide solution appeared to promote both the speed and quality of healing of ESD-induced ulcers by suppressing fibrosis.

Accuracy of biopsy for the preoperative diagnosis of superficial nonampullary duodenal adenocarcinoma.

BACKGROUND AND AIMS: Endoscopic biopsy sampling for the diagnosis of duodenal adenocarcinoma is not perfect. We investigated the accuracy of biopsy specimen diagnoses of superficial nonampullary duodenal epithelial tumors (NADETs). METHODS: Clinicopathologic data were retrospectively reviewed for 95 superficial NADETs from 95 patients who underwent endoscopic resection. Preoperative diagnoses based on biopsy specimens were compared with histologic diagnoses of resected specimens. RESULTS: Among the 21 lesions with biopsy specimen diagnoses of carcinoma, 12 (57.1%) were histologically diagnosed as adenomas after resection. Among the 74 lesions with biopsy specimen diagnoses of adenoma, 15 (20.3%) were histologically diagnosed as carcinomas after resection. The duodenal biopsy specimen predicted final histologic diagnoses of carcinoma with a sensitivity of 37.5% (95% CI, 18.8-59.4), specificity of 83.1% (95% CI, 72.3-91.0), accuracy of 71.6% (95% CI, 61.4-80.4), positive predictive value of 42.9% (95% CI, 21.8-66.0), and negative predictive value of 79.7% (95% CI, 68.8-88.2). Among 61 cases considered suitable for EMR, treatment modality was converted from EMR to endoscopic submucosal dissection because of the nonlifting sign in 15 cases (24.6%). CONCLUSIONS: The accuracy of duodenal biopsy sampling was relatively low. Duodenal biopsy sampling may induce unexpected fibrosis. New endoscopic modalities that can improve preoperative diagnosis yield of NADETs are eagerly awaited.

Endoscopic slip-knot clip suturing method: prospective pilot study (with video).

BACKGROUND AND AIMS: We developed a suturing method with a slip-knot string and clips for a single-channel endoscope. The feasibility of the slip-knot clip suturing method was evaluated in this clinical pilot study. METHODS: Ten patients underwent endoscopic submucosal dissection for colorectal and duodenal tumors 5 cm or less. A slip-knot loop can be tightened when tension is applied to the free end of the string. A clip and string can be passed through an instrument channel (3.2 mm) of a single-channel endoscope. The slip-knot loop is anchored onto the mucosal defect's proximal margin with the clip. Additional clips anchoring the slip-knot loop are placed at the opposite side of the margin. The slip-knot loop is tightened by pulling the string. Additional clips are placed to achieve complete closure. RESULTS: The mean size of resected specimen was 34.4 ± 10.0 mm. The success rate of the slip-knot clip suturing method was 90% (9/10). In the first patient, the string was cut because of friction, and the patient dropped out of the study. After the failure of the first patient, we used wet string to reduce friction, and slip-knot string worked effectively. The mean procedure time was 18.2 ± 3.3 minutes. CONCLUSION: The slip-knot clip suturing method could close large mucosal defects completely using a single-channel endoscope. (Clinical trial registration number: UMIN000017583.).

Endoscopic hand-suturing for defect closure after gastric endoscopic submucosal dissection: a pilot study in animals and in humans.

Background and study aims Mucosal suturing enables reliable and optimal defect closure after endoscopic treatments. We developed and investigated the feasibility of endoscopic hand-suturing (EHS) after gastric endoscopic submucosal dissection (ESD) in porcine in vivo models and in human clinical cases. Patients and methods EHS involving continuous suturing of the mucosal layers using a through-the-scope needle-holder and absorbable barbed suture, was performed after gastric ESD in six live pigs and in eight consecutive patients. Success rates, adverse events, and suture maintenance were subsequently investigated. Results EHS was successfully completed in all six pigs and eight patients (100 %) without severe adverse events. However, at 1 week postoperatively the suture closures had not been maintained in all six porcine cases and in the first four clinical cases. In the later four clinical cases, wider and tight suturing of the mucosal edges ensured that the defects remained closed until postoperative week 4. Conclusion EHS is a feasible procedure that may facilitate secure and refined endoscopic surgeries. Mucosal closure in such cases can be maintained using firm suturing.Clinical trial number: UMIN000017125.

A novel fully synthetic and self-assembled peptide solution for endoscopic submucosal dissection-induced ulcer in the stomach.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) can remove early stage GI tumors of various sizes en bloc; however, success requires reducing the relatively high postprocedure bleeding rate. The aim of this study was to assess the safety and efficacy of a novel, fully synthetic, and self-assembled peptide solution that functions as an extracellular matrix scaffold material to facilitate reconstruction of normal tissues in ESD-induced ulcers. METHODS: Consecutive patients who underwent gastric ESD were prospectively enrolled. Immediately after the resection, the solution was applied to the site with a catheter. Gastric ulcers were evaluated by endoscopy and classified as active, healing, or scarring stages at weeks 1, 4, and 8 after ESD. RESULTS: Forty-seven patients with 53 lesions, including 14 (29.8%) previously on antithrombotic therapy and 2 (4.3%) requiring heparin bridge therapy, were analyzed; 2 patients were excluded, 1 with perforations and 1 with persistent coagulopathy. The mean size of the en bloc resected specimens was 36.5 ± 11.3 mm. The rate of post-ESD bleeding was 2.0% (1/51; 95% CI, 0.03-10.3). Transitional rate to the healing stage of ESD-induced ulcers at week 1 was 96% (49/51). Subsequent endoscopies demonstrated the scarring stage in 19% (9/48) and 98% (41/42) at weeks 4 and 8, respectively. No adverse effects related to this solution occurred. CONCLUSIONS: The use of this novel peptide solution may potentially aid in reducing the delayed bleeding rate by promoting mucosal regeneration and speed of ulcer healing after large endoscopic resections in the stomach. Further studies, particularly randomized controlled studies, are needed to fully evaluate its efficacy. ( CLINICAL TRIAL REGISTRATION NUMBER: 000011548.).

Which part of a porcine stomach is suitable as an animal training model for gastric endoscopic submucosal dissection?

BACKGROUND AND STUDY AIMS: Training using an animal model is generally recommended before performing endoscopic submucosal dissection (ESD) in humans. This study aimed to clarify the suitability of an isolated porcine stomach as an animal training model for gastric ESD. MATERIALS AND METHODS: Study 1: six experienced endoscopists performed ESDs of six simulated lesions located in six locations in an isolated porcine stomach (1, lower third [L]/ greater curvature [Gre]; 2, L/ anterior wall [Ant]; 3, L/ posterior wall [Post]; 4, upper third [U]/ Gre; 5, U/Ant; 6, U/Post). The procedure times (s/cm(2)) were compared among the different lesion locations. A questionnaire (scored 1 - 5) completed by the endoscopists was used to assess the difference in the difficulty compared to the human stomach of the three steps of the ESD procedure (injection, incision and dissection). Study 2: the thicknesses of the mucosal layers were histologically evaluated among the six locations in three porcine and two human stomachs. RESULTS: Study 1: the procedure speed was significantly slower at L/Gre and U/Gre in the porcine stomachs (P = 0.0004). The questionnaire responses revealed a tendency toward similarity between the lower regions of the human and porcine stomachs at L/Ant, L/Post, U/Ant and U/Post during the dissection step (P = 0.056). In contrast, the injection and incision steps at L/Gre in the porcine stomach were shown to differ in difficultly level (both P = 0.0006). Study 2: the mucosal layers in the porcine stomachs were significantly thicker than those in the human stomachs in the lower areas, especially L/Gre. CONCLUSIONS: The difficulty of ESD and the histological features of the porcine stomachs were coincident with those of the human stomachs at L/Ant, L/Post, U/Ant and U/Post. These parts of the porcine stomach may be suitable as animal training models for gastric ESD.