How to master endoscopic submucosal dissection in the USA

The Current Landscape of Endoscopic Submucosal Training in the United States

PURPOSE OF REVIEW

Endoscopic submucosal dissection (ESD) has been found to increase en bloc and R0 resection as well as decrease risk of recurrence. However, despite literature supporting the benefits of endoscopic submucosal dissection, adoption of ESD in the United States has been challenging, driven by factors including requirement for specialized training as well as limitations in training availability.

RECENT FINDINGS

Many devices have been developed to improve ease and therefore adoption for the procedure, with advancements in stability, resection as well as closure of the mucosal defect following resection. While the Japanese model of training in ESD centers around the Master-Apprentice model, this is scarce in the United States. Most US endoscopists therefore must follow other paths to learn and become proficient at ESD. There has been a rapid expansion in literature on ESD, fellowship programs, opportunities for case observation, and significant evolution in ex vivo training models that can assist an endoscopist in receiving training in ESD. Currently, there are three main ways of learning to perform ESD in the United States: 1. Third space endoscopy fellowship; 2. Master-apprentice model; 3. Utilization of live courses and proctored procedures. ESD is the optimal method to ensure en bloc resection of large mucosal neoplasms of the gastrointestinal tract. While several barriers hinder adoption of ESD in the United States, there has been significant development both in procedural and training aspects. Further research and discussions are needed to determine criteria for credentialing and proficiency in ESD.

Robot-assisted gastric endoscopic submucosal dissection significantly improves procedure time at challenging dissection locations

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard treatment for early malignant stomach lesions. However, this procedure is technically demanding and carries a high complication risk. The level of difficulty in performing ESD is influenced by the location of the lesion. In our study, we aimed to investigate and analyze the effectiveness of robot-assisted ESD for lesions situated in challenging locations within the stomach.

METHODS

We developed a gastric simulator that could be used to implement various gastric ESD locations. An EndoGel (Sunarrow, Tokyo, Japan) was attached to the simulator for the dissection procedures. Robot-assisted or conventional ESD was performed at challenging or easy locations by two ESD-trainee endoscopists.

RESULTS

The procedure time was remarkably shorter for robotic ESD than conventional dissection at challenging locations (6.2 vs. 10.2 min, P < 0.05), mainly due to faster dissection (220.3 vs. 101.9 mm2/min, P < 0.05). The blind dissection rate was significantly lower with robotic ESD than with the conventional method (17.6 vs. 35.2%, P < 0.05) at challenging locations.

CONCLUSION

The procedure time was significantly shortened when robot-assisted gastric ESD procedures were performed at challenging locations. Therefore, our robotic device provides simple, effective, and safe multidirectional traction for endoscopic submucosal dissection at challenging locations, thereby reducing difficulty of the procedure.

A novel miniature flexible robotic system for endoscopic mucosal dissection: an animal experimental study

Endoscopic submucosal dissection (ESD) is a standard treatment for early gastrointestinal cancer due to its higher rate of en-bloc resection and lower recurrence rate. However, the technical challenges lead to long learning curve and high risks of adverse events. A gastrointestinal flexible robotic-tool system (GIFTS) was proposed to reduce the difficulty and shorten the learning curve of novices. This is an animal study to evaluate the feasibility of GIFTS in ESD. The GIFTS provides a total of 13 degrees of freedom within 10 mm in diameter and variable stiffness function to achieve endoscopic intervention and submucosal dissection with the cooperation of two flexible robotic instruments. One esophageal and four colorectal ESDs in five porcine models were performed. In all five ESD procedures, the GIFTS was successfully intubated and submucosal dissection was completed without perforation or significant bleeding, and there was no system fault. The mean operative time was 99 min, and the mean size of the specimen was 151 mm2. The fifth experiment showed significantly better results than the first one. In vivo animal experiments confirmed the feasibility of GIFTS in performing ESD. The control of GIFTS is friendly to inexperienced beginners, which will help reduce the technical challenges of ESD and shorten the learning curve of endoscopists.

Novel beagle model of gastric local fibrotic target lesions for the evaluation and training of endoscopic techniques

BACKGROUND

Novel endoscopic techniques used in the treatment of gastric lesions with local submucosal fibrosis need preclinical evaluation and training due to safety limitations. Therefore, the purpose of our study was to establish an animal model of gastric local fibrotic target lesions and assess its feasibility in the evaluation and training of endoscopic techniques.

METHODS

In six experimental beagles, a 50% glucose solution was injected into three submucosal areas of the fundus, body, and antrum of the stomach to create gastric local fibrotic target lesions (experimental group). On post-injection day (PID) 7, the injection sites were assessed endoscopically to confirm the presence of submucosal fibrosis formation, and the dental floss clip traction assisted endoscopic submucosal dissection (DFC-ESD) procedure was performed on the gastric local fibrotic target lesions to confirm its feasibility after endoscopic observation. The normal gastric mucosa of six control beagles underwent the same procedure (control group). All the resected specimens were evaluated by histological examination.

RESULTS

All 12 beagles survived without postoperative adverse events. On PID 7, 16 ulcer changes were observed at the injection sites (16/18) under the endoscope, and endoscopic ultrasonography confirmed the local submucosal fibrosis formation in all ulcer lesions. The subsequent DFC-ESD was successfully performed on the 32 gastric target lesions, and the mean submucosal dissection time in the ulcer lesions was greater than that in the normal gastric mucosa (15.3 ± 5.6 vs. 6.8 ± 0.8 min; P < 0.001). There was no difference in rates of en bloc resection, severe hemorrhage, or perforation between the two groups. Histological analysis of the ulcer lesions showed the absence of epithelial or muscularis mucosae and extensive submucosal fibrous tissue proliferations compared with normal gastric mucosa. Overall, endoscopists had high satisfaction with the realism and feasibility of the animal model.

CONCLUSION

We developed a novel animal model of gastric local fibrotic target lesions to simulate difficult clinical situations, which strongly appeared to be suitable for the preclinical evaluation and learning of advanced endoscopic techniques.

East versus West: Comparisons and Implications in Adaptation to Practice

Endoscopic submucosal dissection (ESD) is the preferred strategy for the resection of large superficial neoplasia throughout the gastrointestinal tract in Asian countries. The transition of ESD to the West has been slower because of various regional and training differences. Nonetheless, over the past couple of decades, the steady growth of ESD mentors in the West and the introduction of viable training pathways and dedicated devices and accessories have led to the increasing adoption of ESD and other third space endoscopic procedures.

Robotic-assisted vs non-robotic traction techniques in endoscopic submucosal dissection for malignant gastrointestinal lesions

Endoscopic submucosal dissection is an effective approach with higher en bloc resection and complete resection rate for superficial gastrointestinal (GI) lesions. However, endoscopic submucosal dissection is technically challenging and associated with several adverse events, such as bleeding or perforations. The single channel flexible endoscope’s intrinsic limitations in preserving visualization of the submucosal dissection plane as compared to laparoscopic surgery are the most common cause of complications during the endoscopic submucosal dissection technique. As a result, traction techniques were created as the endoscope’s second helping hand in order to improve the effectiveness of the endoscopic submucosal dissection method. Trainees can master endoscopic submucosal dissection methods more quickly by using traction techniques. The anatomical location of the lesion plays a major role in determining which traction technique should be employed. An appealing way of traction is robot-assisted endoscopic submucosal dissection, and various types of endoscopic robots that allow bimanual operation are currently being developed. The advent of robot-assisted endoscopic technology ushers in a new era of endoscopic submucosal dissection, and with it come its own unique challenges that remain to be elucidated. Future research and development efforts are needed to focus on pathways and curriculums for trainees to master the currently available traction techniques and provide avenues for the development of newer traction modalities. In this article, we discuss evolution, characteristics, technological improvements and clinical comparisons of both robotic and non-robotic endoscopic traction techniques used in endoscopic submucosal dissection.

Comparisons of outcomes between ProKnife injection endoscopic submucosal dissection and conventional endoscopic submucosal dissection for large gastric lesions in ex vivo porcine model study: A randomized controlled trial

Objective

To compare treatment outcomes between injection endoscopic submucosal dissection using ProKnife (P‐ESD) and conventional ESD (C‐ESD) for gastric lesions.

Methods

In this randomized controlled trial, we compared treatment outcomes of P‐ESD and C‐ESD for simulated gastric lesions ≥3 cm in resected porcine stomachs. Predictive factors associated with ESD difficulties were investigated using logistic regression analysis.

Results

Seventy lesions were screened; however, two lesions were excluded. A total of 12 endoscopists performed 68 ESDs: 34 P‐ESDs and 34 C‐ESDs. The ESD procedure time of P‐ESD (36.3 [28.4–46.8] min) was significantly shorter than that of C‐ESD (46 [36.4–64.6] min; p = 0.0014). The technical success rates did not differ between the P‐ESD and C‐ESD groups (en bloc resection rate, 100% in both groups; complete resection rate, 94.1% and 85.3%, respectively; p = 0.23). The number of injections during P‐ESD (7.5 [6–10] times) was significantly higher than during C‐ESD (4 [3–5] times; p < 0.001), but the total volume of injected solution during P‐ESD (20 [16–26.3] ml) was significantly smaller than during C‐ESD (27.5 [20–31.5] ml; p = 0.0019). In multivariate analysis, less ESD experience (odds ratio [OR], 3.9) and selection of C‐ESD as the ESD method (OR, 3.8) were independent predictive factors associated with ESD difficulties.

Conclusions

Compared with C‐ESD, P‐ESD had a shorter procedure time but also allowed for notable technical success and safety.

The usefulness of combining the pocket-creation method with a traction device using a scissor-type knife for colorectal endoscopic submucosal dissection

INTRODUCTION

Technical issues and long procedure time still remain a concern in colorectal endoscopic submucosal dissection (ESD). We examined the usefulness of combining the pocket-creation method (PCM) with a traction device (S-O clip; SO) using a scissor-type knife (Clutch Cutter 3.5 mm; CC) for decreasing ESD procedure time.

METHODS

We retrospectively analyzed 95 ESD cases of PCM + SO + CC managed from August 2017 to April 2020 and 103 cases of PCM + CC treated from July 2016 to July 2017. We compared these two groups through propensity score matching. The main outcome was the analysis of the ESD procedure times under various conditions in each group.

RESULTS

After matching, 52 cases in the PCM + SO + CC and PCM + CC groups were analyzed. The PCM + SO + CC group showed a significantly shorter ESD procedure time than the PCM + CC group (57.8 ± 31.4 vs. 81.7 ± 33.5 min, p < 0.01). Additionally, the ESD procedure time was significantly shorter in the PCM + SO + CC group than in the PCM + CC group: tumor size (tumor size < 40 mm: 45.6 ± 15.8 vs. 72.7 ± 22.9 min, p < 0.01; tumor size ≥ 40 mm: 83.1 ± 40.1 vs. 111.8 ± 45.3 min, p = 0.04), tumor location (right side: 64.7 ± 33.3 vs. 81.0 ± 29.7 min, p = 0.03; left side: 50.5 ± 28.0 vs. 82.3 ± 36.9 min, p < 0.01), tumor morphology (polypoid: 39.2 ± 18.6 vs. 74.7 ± 28.6 min, p < 0.01; nonpolypoid: 62.3 ± 32.3 vs. 84.5 ± 35.2 min, p < 0.01), endoscopist (expert: 67.3 ± 41.2 vs. 91.9 ± 40.2 min, p = 0.02; nonexpert: 50.4 ± 18.3 vs. 73.6 ± 24.9 min, p < 0.01), and fibrosis (severe fibrosis: 82.0 ± 20.5 vs. 99.8 ± 40.4 min, p = 0.169; non-severe fibrosis: 52.1 ± 23.8 vs. 75.6 ± 29.0 min, p < 0.01).

CONCLUSIONS

The combination of the PCM and SO using CC achieved a reduction in the colorectal ESD procedure time.

Minimally Invasive Endoscopic and Surgical Management of Rectal Neoplasia

Rectal cancer demonstrates a characteristic natural history in which benign rectal neoplasia precedes malignancy. The worldwide burden of rectal cancer is significant, with rectal cancer accounting for one-third of colorectal cancer cases annually. The importance of early detection and successful management is essential in decreasing its clinical burden. Minimally invasive treatment of rectal neoplasia has evolved over the past several decades, which has led to reduced local recurrence rates and improved survival outcomes. The approach to diagnosis, staging, and selection of appropriate treatment modalities is a multidisciplinary effort combining interventional endoscopy, surgery, and radiology tools. This review examines the currently available minimally invasive endoscopic and surgical management options of rectal neoplasia.

Pilot prospective study on formal training in per-oral endoscopic myotomy (POEM) during advanced endoscopy fellowship

Background and study aims  Gastroenterology societies have recently proposed core curricula for training in per-oral endoscopic myotomy (POEM) based on expert opinion with limited data on its applicability for advanced endoscopy fellowship (AEF) trainees. We prospectively evaluated the feasibility of a structured POEM training curriculum during a dedicated AEF and the trainee's performance during independent practice. Methods  This was a single-center prospective study evaluating a trainee's performance of POEM using a structured assessment tool (POEMAT) to assess core cognitive and technical skills. The trainee's performance was then prospectively assessed during the first 12 months of independent practice. Results  The trainee, who had not prior background in submucosal endoscopy, first observed 22 POEM cases followed by 35 hands-on procedures during his advanced endoscopy fellowship. Based on the POEMAT, submucosal entry and mucosal incision closure were the most challenging technical aspects, while cognitive skills were uniformly attained early in training. Overall, the trainee was able to cross the threshold for competence in his POEMAT performance score in 15 of his last 18 cases (83.3 %). The trainee performed 16 POEMs (baseline mean Eckardt 7.2) in his first 12 months of independent practice. Mean procedural time was 79.8 minutes (interquartile range: 67-94 minutes minutes) with no adverse events. Clinical success (Eckardt score < 3) was achieved in 100 % of the cases at a median follow-up of 20 weeks. Conclusions  Results from this pilot study support the adoptability of the recently proposed core curricula for POEM training within the context of a dedicated AEF and provide a potential blueprint for future studies of performance in POEM among trainees.

Advances in endoscopic therapy using grasping-type scissors forceps (with video)

Endoscopic submucosal dissection (ESD) is a globally accepted minimally invasive therapy for early-stage gastrointestinal tract tumors. Although numerous electrosurgical knives have been developed for ESD, technical difficulties and high complication rates (bleeding and perforation) have limited their use worldwide. The grasping-type scissors forceps [clutch cutter (CC)] is the first forceps-type resection device developed with reference to hemostatic forceps. The aim was to allow easy and safe ESD throughout the gastrointestinal tract, as a biopsy technique, using one device. The CC can grasp the target tissue accurately and pull it away from the underlying muscle layer prior to energizing the tissue, for safe and effective incision and hemostasis during ESD. Reported clinical studies showed that ESD using the CC (ESD-CC) is a safe (perforation rate: 0%-3.6%; delayed bleeding rate: 0%-4.2%), technically efficient (en-bloc resection rate: 88.9%-100%), and single-device method for dissecting early-stage gastrointestinal tract tumors. The ESD-CC technique is simple and easy to learn because it can be completed simply by repeating the grasp, pull, and coagulate and/or incise actions using an electrosurgical current. The reported self-completion rate by non-experts was significantly better with the CC than with conventional knives (61.7% vs 24.5%, respectively; P < 0.001). Furthermore, the CC is used for other endoscopic therapies, such as endoscopic polypectomy for large pedunculated polyps, endoscopic myotomy for Zenker’s diverticulum, endoscopic treatment of buried bumper syndrome, and endoscopic necrosectomy for wall-off pancreatic necrosis. The initial reports using CC for these therapies have shown favorable results. In this review, we describe the structural features of the CC, how to use the instrument, efficacies of ESD-CC, and other unique endoscopic therapies using the CC.

Scissor-type knife improves the safety of endoscopic submucosal dissection (ESD) among endoscopists without experience in ESD: a randomized ex vivo study

Background and study aims  Endoscopic submucosal dissection (ESD) is technically challenging, difficult to learn, and carries a substantial risk of perforation, all of which remain significant barriers to its adoptability. We aimed to determine whether use of a novel scissor-type knife improved efficacy and safety among novice performers of ESD. Materials and methods  Following a brief didactic session on ESD, participants performed ESD of two lesions (2 cm diameter) in an ex vivo porcine gastric model. One resection was performed with a conventional knife and the other with the scissor knife (order of knife randomized). We recorded procedure time, successful en bloc resection, and adverse events (including full-thickness perforation and muscle injury) for each dissection. Participants completed a post-study survey. Results  10 endoscopists (8 trainees, 2 staff) considered novices in ESD participated. Compared with the conventional knife, use of the scissor knife was associated with a significantly shorter time to completion of submucosal dissection (mean 6.2 [SD 5.6] vs. 15.6 [SD 15.6] minutes; P  = 0.04) and total procedure time was not significantly different (22.1 [SD 13.3] vs. 24.9 [SD 26.5] minutes; P  = 0.65). Scissor knife use was also associated with a significantly lower proportion of perforation and/or muscle injury (10.0 % vs. 70.0 %; P  < 0.01) and proportion of muscle injury alone (10.0 % vs. 60.0 %; P  = 0.02). Conclusions  Among novices performing ESD on an ex vivo animal model, use of a scissor knife was associated with a significantly lower proportion of adverse events without prolonging procedure time. Scissor-type knives may improve ESD safety, at least among novices.

Endoscopic Submucosal Dissection in North America: A Large Prospective Multicenter Study

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) in Asia has been shown to be superior to endoscopic mucosal resection (EMR) and surgery for the management of selected early gastrointestinal cancers. We aimed to evaluate technical outcomes of ESD in North America.

METHODS

We conducted a multicenter prospective study on ESD across 10 centers in the United States and Canada between April 2016 and April 2020. End points included rates of en bloc resection, R0 resection, curative resection, adverse events, factors associated with failed resection, and recurrence post-R0 resection.

RESULTS

Six hundred and ninety-two patients (median age, 66 years; 57.8% were men) underwent ESD (median lesion size, 40 mm; interquartile range, 25-52 mm) for lesions in the esophagus (n = 181), stomach (n = 101), duodenum (n = 11), colon (n = 211) and rectum (n = 188). En bloc, R0, and curative resection rates were 91.5%, 84.2%, and 78.3%, respectively. Bleeding and perforation were reported in 2.3% and 2.9% of the cases, respectively. Only 1 patient (0.14%) required surgery for adverse events. On multivariable analysis, severe submucosal fibrosis was associated with failed en bloc, R0, and curative resection and higher risk for adverse events. Overall recurrence was 5.8% (31 of 532) at a mean follow-up of 13.3 months (range, 1-60 months).

CONCLUSIONS

In this large multicenter prospective North American experience, we demonstrate that ESD can be performed safely, effectively, and is associated with a low recurrence rate. The technical resection outcomes achieved in this study are in line with the current established consensus quality parameters and further support the implementation of ESD for the treatment of select gastrointestinal neoplasms; ClinicalTrials.gov, Number: NCT02989818.

Endoscopic submucosal dissection (ESD): how do Western endoscopists value animal models?

INTRODUCTION

Endoscopic Submucosal Dissection (ESD)was introduced in the West later than in the East. Our aim was to assess how Western endoscopists performing ESD have been trained and how they value animal models for training.

MATERIAL AND METHODS

An online survey regarding training in ESD was sent to Western endoscopists who published articles on advanced resection techniques.

RESULTS

From 279 endoscopists, 58 (21%) completed the questionnaire, of which 50 confirmed performance of clinical ESD. Endoscopists had a median of 15 years of endoscopic experience (IQR 9.75-20.25) and all of them were performing conventional EMR, before starting ESD. Prior to clinical ESD, 74% (n = 37) underwent training with ex vivo models, 84% (n = 42) with live animal models and 92% (n = 46) with at least, one of the two models. After starting clinical ESD, as trainers, 52% (n = 26) were involved with ex vivo and 60% (n = 30) with live animal models. Personal usefulness of ex vivo and live animal models was rated with a median of 9 (IQR 8-10) and 10 (IQR 8-10), out of 10, respectively. Courses with ex vivo and live animal models were considered a prerequisite before clinical practice by 84% (n = 42) and 78% (n = 39), respectively.

CONCLUSIONS

Western endoscopists have extensive endoscopic experience before starting ESD. The majority had pre-clinical training with ex vivo and live animal models and more than half are acting as trainers of other endoscopists with these models. Animal models are considered very useful and deemed a prerequisite before clinical practice by the majority of the endoscopists.

A Template for Curriculum Development to Teach Complex Surgical or Endoscopic Techniques With Logistical Challenges

OBJECTIVE

The current, unprecedented pace of change in medicine challenges healthcare professionals to stay up-to-date. To more effectively disseminate new surgical or endoscopic techniques a modern paradigm of training is required. Our aim was to develop a curricular framework for complex techniques that provide logistical challenges to training in order to increase safe, effective use. We use colonic endoscopic submucosal dissection (cESD) as an example.

DESIGN

Curriculum development followed a multistep process representing best practice in training and education. First, a Clinical Needs Assessment established the demand for/sustainability of training. A Training Needs Analysis then identified the knowledge, skills, and attitudes required to perform cESD. A modified Delphi process defined desired learner characteristics, identified indications/contraindications to cESD, and developed a procedural task list. A pilot simulation program gathered feedback from cESD faculty experts and learners. Finally, a Behavioral Observation Scale was developed as a clinical assessment tool to assess procedural performance.

SETTING

The Houston Methodist Institute for Technology, Innovation and Education.

PARTICIPANTS

The first Curriculum Design Summit engaged 11 clinical SMEs, 4 education and training SMEs, 3 market development SMEs, and 1 medical device research and design engineer. The second Curriculum Design Summit engaged 10 clinical SMEs, 4 education and training SMEs, and 4 market development SMEs. We also engaged 12 Learner SMEs at both hands-on pilot courses who currently are training to perform cESD.

RESULTS

Desired learner criteria were defined (e.g., in practice >2 years, available case volume ≥25/year) to ensure ability and motivation of learners. Lesions were classified by (1) suitability for cESD (Clinical T1N0M0, Paris 0-IIa +1s  > 2 cm, 0-IIc + IIa, 0-IIc), and (2) suitability for trainee experience level. A comprehensive cESD task list was constructed and an assessment tool created based on SME review of key characteristics (e.g., comprehensiveness and usability).

CONCLUSION

We describe a comprehensive framework to develop educational curricula for complex surgical/endoscopic techniques with logistical challenges. To illustrate the sustainability of this training model and impact on patient outcomes, we plan to further develop and implement this program nationally.

The status of training in new technologies in advanced endoscopy: from defining competence to credentialing and privileging

The landscape of advanced endoscopy continues to evolve as new technologies and techniques become available. Although postgraduate advanced endoscopy fellowships have traditionally centered on ERCP and diagnostic EUS, the breadth of training has increased over the years in response to the ever-growing demand for therapeutic endoscopy. The increasing diversity and complexity of emerging endoscopic techniques accompanied by the shift in focus toward competency-based medical education requires innovative changes to the curriculum that will ensure adequate training yet without compromising best patient practices. The purpose of this review is to highlight the expansive array of advanced endoscopic procedures and the challenges of both defining and measuring competence during training. All authors are interventional endoscopists at their respective institutions performing these complex procedures, as well as training fellows in these techniques. We share our perspectives based on our experience navigating through these issues at our institutions and discuss strategies to standardize training and how to potentially incorporate these measures in the process of credentialing and privileging in endoscopy.

Current state of education and training for endoscopic submucosal dissection: Translating strategy and success to the USA

Endoscopic submucosal dissection (ESD) is a rigorous and technically sophisticated method for removal of lesions within the gastrointestinal tract. Despite having advantages of en-bloc resection of lesions, regardless of size, and widespread use in Japan and Asia, ESD has not become widely adopted in the USA for a variety of reasons. Based upon Japanese education and the master-apprentice model, modification to the education system and additional techniques designed to facilitate broader adoption are required for trainees in the USA. This article will review the current state of education and training for ESD in the USA.

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.).

Pathologic Evaluation of Large Colorectal Endoscopic Submucosal Dissections: An Analysis of 279 Cases With Emphasis on the Importance of Multidisciplinary Work and Establishing Examination Protocols

Background. Endoscopic submucosal dissections (ESDs) allow removal of large gastrointestinal tumors and help patients avoid major oncologic surgery. In this study, the challenges and development of approaches toward successfully handling ESDs were analyzed in 279 colorectal specimens (114 rectal, 47 left, 118 right colonic; 90% adenoma with/without carcinoma). Methods. Each specimen was processed according to an established protocol including gross photography, mapping, and total submission for histopathologic examination. Results. Mean lesion size was 4.2 cm (range: 0.5-22 cm; 28% ≥5 cm; 6% ≥10 cm). Invasive carcinoma was present in 38 cases (14%), which had a mean overall tumor size of 3.8 cm (range: 1.1-17.5 cm), and mean largest size of the invasive component was 0.93 cm (range: 0.04-3 cm). Fifteen cases were staged as pT1a (submucosal invasion of <1000 µm) and 13 cases as pT1b (submucosal invasion of ≥1000 µm). En-bloc and R0 resection rates were 99.3% and 90.6%, respectively. Conclusion. Various histopathologic challenges were encountered, which were carefully evaluated by dedicated pathologists with familiarity to the subtleties in handling and reporting these specimens. We recommend these specimens to be prepared in the endoscopy suite, submitted to the Pathology Department oriented, pinned, and placed into copious amount of fixative. Total sampling, gross photography, mapping, and proper fixation are crucial components in the histopathologic evaluation. Micromeasurement of invasion depth and substaging per European/Japanese guidelines as well as accurate measurement of the distance from the resection margins are highly recommended. In conclusion, ESD is an adequate method that can be successfully implemented in a tertiary care center to perform en-bloc and margin-free resections of clinically selected large colorectal superficial lesions.

Efficacy of scissor-type knives for endoscopic mucosal dissection of superficial gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) for superficial gastrointestinal neoplasms has become widespread. However, certain aspects of the procedure remain difficult to manage, such as intraoperative bleeding and perforation. There are two kinds of scissor-type knife: the Clutch Cutter (Fujifilm Co., Tokyo, Japan) and the SB knife (Sumitomo Bakelite Co., Tokyo, Japan). These knives have different features from other types of ESD knives and enable the performance of all ESD procedures, including mucosal incision, submucosal dissection, and hemostasis. The standard approach with scissor-type knives involves first grabbing the tissue and then incising or dissecting it. Theoretically, perforation as a result of unintentional movement should never happen with scissor-type knives compared to needle- or blade-type knives, which may induce perforation through unintentional movement. Moreover, the rates of severe bleeding and self-completion of ESD with scissor-type knives by non-experts were reported to be significantly better than for other knives. Thus, scissor-type knives can resolve these problems and help to further standardize ESD globally. In this review, we summarize reports on the efficacy of such scissor-type knives for ESD of gastrointestinal tumors. We also present the pocket-creation method and the application of traction devices, such as dental floss and S-O clips (Zeon Medical Co., Tokyo, Japan) for improving the performance of ESD with a Clutch Cutter.

Safety and efficacy of endoscopic submucosal dissection for rectal neoplasia: a multicenter North American experience

Background and aims  Rectal lesions traditionally represent the first lesions approached during endoscopic submucosal dissection (ESD) training in the West. We evaluated the safety and efficacy of rectal ESD in North America. Methods  This is a multicenter retrospective analysis of rectal ESD between January 2010 and September 2018 in 15 centers. End points included: rates of en bloc resection, R0 resection, adverse events, comparison of pre- and post-ESD histology, and factors associated with failed resection. Results  In total, 171 patients (median age 63 years; 56 % men) underwent rectal ESD (median size 43 mm). En bloc resection was achieved in 141 cases (82.5 %; 95 %CI 76.8-88.2), including 24 of 27 (88.9 %) with prior failed endoscopic mucosal resection (EMR). R0 resection rate was 74.9 % (95 %CI 68.4-81.4). Post-ESD bleeding and perforation occurred in 4 (2.3 %) and 7 (4.1 %), respectively. Covert submucosal invasive cancer (SMIC) was identified in 8.6 % of post-ESD specimens. There was one case (1/120; 0.8 %) of recurrence at a median follow-up of 31 weeks; IQR: 19-76 weeks). Older age and higher body mass index (BMI) were predictors of failed R0 resection, whereas submucosal fibrosis was associated with a higher likelihood of both failed en bloc and R0 resection. Conclusion  Rectal ESD in North America is safe and is associated with high en bloc and R0 resection rates. The presence of submucosal fibrosis was the main predictor of failed en bloc and R0 resection. ESD can be considered for select rectal lesions, and serves not only to establish a definitive tissue diagnosis but also to provide curative resection for lesions with covert advanced disease.

How to Learn and Perform Endoscopic Submucosal Dissection and Full-Thickness Resection in the Colorectum in the United States

Pioneered in Japan to address the limitations of endoscopic mucosal resection in the stomach, endoscopic submucosal dissection (ESD) has been applied throughout the gastrointestinal tract, including the colorectum. ESD is technically challenging and has been slowly gaining traction in the West. However, for the committed and resourceful endoscopist, proficiency in ESD can still be achieved. Moreover, improvement in techniques and devices are likely to ease the learning curve while improving procedural duration, safety, and efficacy of colorectal ESD. This article reviews challenges and methods in learning ESD in the United States and provides a primer on performing ESD and full-thickness resection in the colorectum.

Topographic mapping of a specimen after endoscopic submucosal dissection

Background and study aims  Mapping of pathologic specimens after endoscopic submucosal dissection (ESD) is common practice in Asian countries, especially in Japan. However, there is a lack of awareness for this technique in Europe. In this report, we demonstrate the feasibility and benefits of topographic mapping in a Western setting.