Training in endoscopic submucosal dissection from a Western perspective

Learning curve for endoscopic submucosal dissection (ESD) in the United States: Large, untutored, single-operator experience

Background and study aims Endoscopic submucosal dissection (ESD) allows removal of tumors en-bloc. Western adoption of ESD has been hindered by its steep learning curve. Western data regarding ESD learning curve are limited. We analyzed the learning curve of a single endoscopist at a tertiary referral center in the United States. Patients and methods All consecutive ESDs performed by a single endoscopist at a tertiary referral center in the United States from 2015 through 2022 were identified. Descriptive statistics and CUSUM analysis were used to describe the learning curve for en-bloc, R0 resection, and resection speed. Results In our study, 503 patients with 515 lesions were included. Severe submucosal fibrosis was found in 17% of the lesions. The rates of en-bloc, R0, and curative resections were 81.9%, 71.1%, and 68.4%, respectively. CUSUM analysis showed that the learning curve plateaued at 268, 347, and 170 cases for en-bloc resection, R0 resection, and achieving a resection speed > 9 cm 2 /hr. Fibrosis significantly affected the R0 resection rate in the regression analysis (95% confidence interval 0.21-0.55). In colonic ESD curve analysis, the learning plateau was reached after 185 cases for both en-bloc and R0 resection. Conclusions Following ex-vivo training in an animal model, an untutored expert operator achieved competency in ESD between 250 and 350 procedures. Our data can inform development of future training programs in the West.

Extrapancreatic Advanced Endoscopic Interventions

As the field of interventional endoscopy advances, conditions that were once treated with surgery are increasingly being treated with advanced endoscopy. Endoscopy is now used for treatment of achalasia, bariatric procedures for obesity; resection of early-stage malignancies in the gastrointestinal tract; and placement of lumen-apposing metal stents in the treatment of biliary obstruction, gastric outlet obstruction, cholecystitis, and drainage of nonpancreatic-related fluid collections or abscesses. Knowledge of the novel terminology, procedural details, expected postintervention imaging findings, and potential complications is vital for radiologists because these procedures are rapidly becoming more mainstream in daily practice. These procedures include peroral endoscopic myotomy for the treatment of achalasia and other esophageal motility disorders; endoscopic sleeve gastroplasty and placement of an intragastric balloon for weight loss; endoscopic submucosal dissection in the resection of tumors of the gastrointestinal tract; and therapeutic endoscopic-guided procedures for the treatment of biliary obstruction, gastric outlet obstruction, acute cholecystitis, and drainage of nonpancreatically related fluid collections. Patients benefit from these minimally invasive procedures, with potential improvement in morbidity and mortality rates, decreased length of hospital stay, and decreased health care costs when compared with the surgical alternative. Complications of these procedures include leaks or perforations, infections or abscesses, fistulas, and occlusion and migration of stents. An invited commentary by Pisipati and Pannala is available online. ^©RSNA, 2022.

Hybrid endoscopic mucosal resection and full-thickness resection for large colonic polyps harboring a small focus of invasive cancer: a case series

Endoscopic treatment of large laterally spreading tumors (LSTs) with a focus of submucosally invasive colorectal cancer (T1 CRC) can be challenging. We evaluated outcomes of a hybrid resection technique using piecemeal endoscopic mucosal resection (pEMR) and endoscopic full-thickness resection (eFTR) in patients with large colonic LSTs containing suspected T1 CRC. Six hybrid pEMR-eFTR procedures for T1 CRCs were registered in a nationwide eFTR registry between July 2015 and December 2019. In all cases, the invasive part of the lesion was successfully isolated with eFTR; with eFTR, histologically complete resection of the invasive part was achieved in 5 /6 patients (83.3 %). No adverse events occurred during or after the procedure. The median follow-up time was 10 months (range 6-27), with all patients having undergone ≥ 1 surveillance colonoscopy. One patient had a small adenomatous recurrence, which was removed endoscopically. In conclusion, hybrid pEMR-eFTR is a promising noninvasive treatment modality that seems feasible for a selected group of patients with large LSTs containing a small focus of T1 CRC.

Management of early gastric cancer meeting criteria for endoscopic resection: US population-based study

Background and study aims  The goal of this study was to assess surgical resection (SR) of early gastric cancer (EGC) fitting Japanese Gastric Cancer Association (JGCA) endoscopic resection (ER) criteria. Patients and methods  We analyzed EGC data from the national Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015. Results  A total of 2219 EGC cases were identified (1074 T1a and 1145 T1b). Of them, 409 met absolute criteria, 219 met expanded 1, 529 expanded 2, and 229 expanded 3. 259 lesions were treated endoscopically while 1007 were surgically resected (20.5 % vs 79.5 %, P  = 0.0001). Temporal analysis showed that the frequency of ER steadily increased while SR proportionally decreased during the study period. Cox proportion regression analysis adjusting for confound variables (including age, gender, and race) showed no significant difference in the risk of mortality following either surgery or endoscopy. Conclusions  EGC can be safely treated with ER. However, EGC meeting JGCA ER criteria is largely treated with SR in the United States.

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.

Safety and histologic outcomes of endoscopic submucosal dissection with a novel articulating knife for esophageal neoplasia

BACKGROUND AND AIMS

Treatment of large esophageal neoplasia is gradually evolving from piecemeal to en bloc resections. Endoscopic submucosal dissection (ESD) is known to achieve more complete resections than piecemeal EMR for large lesions, yet it remains underused in the West because of technical and safety concerns with traditional electrosurgical knives. We aimed to evaluate a novel endoscopic articulating knife used with ESD (ESD-AR) to determine its safety and efficacy for large esophageal neoplasms in comparison with EMR.

METHODS

We retrospectively studied clinically indicated cases of ESD-AR and EMR for esophageal lesions that were 15 mm or greater. All EMR cases had at least 3 simultaneous EMRs to adequately compare resection area. Rates of perforation, GI bleeding, technical performance, and pre- and postendoscopic resection diagnoses were evaluated.

RESULTS

Seventy-two ESD-AR and 72 widespread EMR cases were evaluated for Barrett's esophagus (56%), adenocarcinoma (36%), squamous nodularity (2%), and squamous cell carcinoma (6%). There were no statistical differences in age, sex, Barrett's esophagus length, and lesion or resection size between the 2 groups. No perforations occurred. Two adverse events were recorded with ESD-AR and none with EMR (3% vs 0%, P = .50); these were associated with anticoagulation use (P = .04) and greater resection area (P = .02). There were more upgraded diagnoses post-ESD versus EMR (27% vs 12%, P = .05).

CONCLUSIONS

ESD-AR by an experienced endoscopist has a comparable safety profile with widespread EMR for large esophageal neoplasia and may have advantages for diagnostic staging.

Update on the Diagnosis and Management of Gastric Intestinal Metaplasia in the USA

Gastric intestinal metaplasia (GIM) is a premalignant condition that can lead to intestinal-type gastric adenocarcinoma. It is characterized by a change in the gastric mucosa to a small-intestinal phenotype. Infection with Helicobacter pylori is the most common factor associated with GIM. Although GIM is typically a histologic diagnosis, various techniques have been developed to enable the endoscopic identification of GIM. There are presently no widely accepted guidelines on screening and surveillance strategies in patients with GIM in the USA. The aim of this review is to provide an update regarding the problem, diagnosis, and management of GIM in the USA.

AGA Institute Clinical Practice Update: Endoscopic Submucosal Dissection in the United States

Endoscopic submucosal dissection (ESD) is an established endoscopic resection method in Asian countries, which is increasingly practiced in Europe and by early adopters in the United States for removal of early cancers and large lesions from the luminal gastrointestinal tract. The intent of this expert review is to provide an update regarding the clinical practice of ESD with a particular focus on its use in the United States. This review is framed around the 16 best practice advice points agreed upon by the authors, which reflect landmark and recent published articles in this field. This expert review also reflects our experience as advanced endoscopists with extensive experience in performing and teaching others to perform ESD in the United States. Best Practice Advice 1: Endoscopic submucosal dissection should be recognized as a mature endoscopic technique that enables complete removal of lesions that are too large for en bloc endoscopic mucosal resection or are at increased risk of containing cancer. Best Practice Advice 2: The safety and feasibility of endoscopic submucosal dissection for early gastric cancer is well established. The absolute indications for curative endoscopic resection include moderately and well-differentiated, nonulcerated, mucosal lesions that are ≤2 cm in size. Best Practice Advice 3: Other relative (expanded) indications for gastric endoscopic submucosal dissection include moderately and well-differentiated superficial cancers that are >2 cm, lesions ≤3 cm with ulceration or that contain early submucosal invasion, and poorly differentiated superficial cancers ≤2 cm in size. The risk of lymph node metastasis when endoscopic submucosal dissection is performed for these indications is higher than when it is performed for absolute indications but remains acceptably low. Best Practice Advice 4: Endoscopic submucosal dissection may be considered in selected patients with Barrett's esophagus with the following features: large or bulky area of nodularity, lesions with a high likelihood of superficial submucosal invasion, recurrent dysplasia, endoscopic mucosal resection specimen showing invasive carcinoma with positive margins, equivocal preprocedural histology, and intramucosal carcinoma. Best Practice Advice 5: Endoscopic submucosal dissection is the primary modality for treatment of squamous cell dysplasia and cancer confined to the superficial esophageal mucosa. Any degree of submucosal invasion caries an increased risk of lymph node metastasis and alternative/additional therapy should be considered. Best Practice Advice 6: Duodenal endoscopic submucosal dissection is associated with an increased risk of intraprocedural perforation and delayed adverse events. Duodenal endoscopic submucosal dissection should be limited to endoscopists with extensive experience in performing endoscopic submucosal dissection in other locations. It is strongly suggested that endoscopists in the United States refrain from performing duodenal endoscopic submucosal dissection during the early phase of their endoscopic submucosal dissection practice. Best Practice Advice 7: All colorectal lesions should be evaluated for suitability for endoscopic resection. Accumulating evidence has shown that the majority of colorectal neoplasms without signs of deep submucosal invasion or advanced cancer can be treated by advanced endoscopic resection techniques. Best Practice Advice 8: Colorectal neoplasms containing dysplasia confined to the mucosa have no risk for lymph node metastasis and endoscopic resection should be considered as the criterion standard. Best Practice Advice 9: Large (>2 cm) colorectal lesions frequently (>43%) require piecemeal removal when endoscopic mucosal resection is used, which is associated with increased (up to 20%) rates of recurrent neoplasia. Endoscopic submucosal dissection enables higher rates of en bloc resection and lower recurrence rates for these lesions. Patients with large complex colorectal polyps should be referred to a high-volume, specialized center for endoscopic removal by endoscopic mucosal resection or endoscopic submucosal dissection. Best Practice Advice 10: Endoscopic resection for colorectal lesions offers significant cost benefit compared with surgery, and case-based endoscopic submucosal dissection selection for high-risk lesions could offer cost savings. Best Practice Advice 11: Endoscopists in the United States embarking on performing endoscopic submucosal dissection should be familiar with currently available endoscopic tissue closure devices. Both clip closure and endoscopic suturing techniques have been shown to be effective in managing intraprocedural perforation. Complete closure of a post-endoscopic submucosal dissection site may be considered in certain circumstances based on patient factors, procedural factors, and the location of the lesion. Best Practice Advice 12: Careful coagulation of exposed blood vessels in the resection site may reduce the risk of delayed bleeding after endoscopic submucosal dissection. The use of low-voltage coagulation current is recommended for this technique. Best Practice Advice 13: Endoscopists should affix the endoscopic submucosal dissection specimen to a flat surface (eg, pin the specimen to cork board) and immerse it in formalin. An expert gastrointestinal pathologist should evaluate the specimen for margin involvement, degree of differentiation, presence or absence of lymphovascular invasion, depth of submucosal invasion (if present), and tumor budding. Best Practice Advice 14: Acquiring high-level competency in endoscopic submucosal dissection is achievable in the United States. Alternative educational models should be used in the United States because of the limited number of experts and the differing prevalence of gastrointestinal luminal diseases as compared with Asia. Best Practice Advice 15: The endoscopic submucosal dissection educational model most suited for the current environment in the United States is a stepwise approach consisting of didactic self-study, attending training courses with increasing levels of complexity, self-practice on animal models, and observation of live cases performed by experts. Endoscopists should perform their initial endoscopic submucosal dissections on patients with lesions that have well-established indications for endoscopic submucosal dissection and are of the lowest technical complexity. Best Practice Advice 16: Endoscopists in the United States who perform endoluminal resection should educate referring physicians to avoid practices that may induce submucosal fibrosis hampering future endoscopic mucosal resection or endoscopic submucosal dissection. These practices include tattooing in close proximity to or beneath a lesion for marking and partial snare resection of a portion of a lesion for histopathology.

How to master endoscopic submucosal dissection in the USA

Endoscopic submucosal dissection (ESD) is an established technique for the endoscopic therapy of dysplastic and early cancerous lesions throughout the gastrointestinal tract. The procedure requires both a sophisticated knowledge for lesion characterization and high-level endoscopic skills. As a result, the learning curve is very steep and, in Japan, it takes years to gain proficiency under the traditional Master-Apprentice teaching model. At present, as a result of multiple limitations, this training model is not applicable to the USA. Nevertheless, a unique, multipronged, stepwise approach has emerged as a viable pathway to train US endoscopists in ESD. Although this approach deserves refinement, it has already led to the expansion of ESD in the USA, has contributed to the widening of the indications for ESD, and has further developed ESD techniques. Multiple challenges remain, but they can be overcome by active collaboration between Japanese and US endoscopists and professional societies. The robust interest in ESD in the USA has drawn industry attention with a few innovations already coming to fruition and many more in development.