A colonoscopic overtube system that creates a 'therapeutic zone' and permits retraction facilitates endoscopic submucosal dissection, was associated with fewer deep bowel wall injuries and instrument exchanges, and required less lifting solution vs classic endoscopic submucosal dissection in an ex vivo bovine model.

INTRODUCTION: Endoscopic submucosal dissection (ESD) is the 'gold standard' for large flat polyps; nevertheless, the rate of adoption in the USA is low. In ESD, the polyp is 'surgically' detached with a needle knife after a submucosal lift; gravity and the dissection cap are used for retraction. ESD would be easier if active retraction were possible. In an ex vivo bovine colon model, this study assessed an overtube system (Boston Scientific ORISE Tissue Retraction System, TRS) that permits retraction and creates 'an operative field' for removal of rectal/sigmoid lesions. METHOD: Classic ESD (C-ESD) was compared to TRS-facilitated ESD (TRS-ESD). Cleaned/preserved bovine large bowel was used, and two 2-cm 'lesions'/colon were branded onto the mucosal surface 25 and 35 cm from the anus. Submucosal saline lifts were made using a thin catheter and a standard needle knife. We tracked case length, number of instrument exchanges (to refresh lift), the volume of lift solution, the fullness of resection, and deep muscle injuries. RESULTS: Fifty ESDs were carried out in 25 colons (25 C-ESD, 25 TRS-ESD). Complete resections were noted in all cases. The TRS method required fewer instrument exchanges (median 5) vs C-ESD (median 9, p < 0.0001) and less lift solution (median 39 ml) than the C-ESD cases (median 55 ml, p = 0.0003). TRS-ESD was associated with fewer deep muscle injuries (median 2) than C-ESD (median 3, p = 0.0191). Finally, the TRS group's median case length (34.5 min) was shorter than that of C-ESD (41 min, p = 0.0543). CONCLUSION: The TRS system provides retraction and facilitates ESD regarding the number of lift injections, the volume of lift solution needed, and avoidance of muscle injuries. Of note, there is an apparent TRS learning curve, and the device mandates a distal-to-proximal approach and initial 360 degree mucosal incision. Further study is warranted.

AGA Clinical Practice Update on Surveillance After Pathologically Curative Endoscopic Submucosal Dissection of Early Gastrointestinal Neoplasia in the United States: Commentary.

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update was to review the available evidence and provide expert advice regarding surveillance using endoscopy and other relevant modalities after removal of dysplastic lesions and early gastrointestinal cancers with endoscopic submucosal dissection deemed to be pathologically curative. This Clinical Practice Update was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors, who are advanced endoscopists with high-level expertise in performing endoscopic submucosal dissection to treat dysplasia and early cancers in the luminal gastrointestinal tract.

Best Practices in Surveillance for Barrett's Esophagus.

Barrett's esophagus is the precursor lesion for esophageal adenocarcinoma. The goals of endoscopic surveillance are to detect dysplasia and early esophageal adenocarcinoma in order to improve patient outcomes. Despite the ongoing debate regarding the efficacy of surveillance, all current gastrointestinal societies recommend surveillance at this time. Optimal surveillance technique includes adequate inspection time, evaluation using high-definition white light and chromoendoscopy, appropriate documentation of the metaplastic segment using the Prague C & M criteria as well as the Paris classification should lesions be found, utilization of the Seattle biopsy protocol, and endoscopic resection of visible lesions.

Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection.

Therapeutic endoscopy is an emerging field within general surgery. This article explores the evidence for and usage of endoscopic mucosal resection and endoscopic submucosal dissection throughout the gastrointestinal tract. We aim to educate surgeons and provide an understanding of these techniques. With education and appropriate training, the surgeon will gain confidence and hopefully adopt these tools into their daily practice.

Protocol for expanded indications of endoscopic submucosal dissection for early gastric cancer in China: a multicenter, ambispective, observational, open-cohort study.

BACKGROUND: The main treatment methods for early gastric cancer (EGC) include endoscopic submucosal dissection (ESD) and radical gastrectomy. However, appropriate treatment for patients who exceed the absolute indications for ESD remains unestablished. In China, evidence-based medicine for the expanding indications of ESD and accurate diagnostic staging for EGC patients are lacking. Thus, clinical studies involving Chinese patients with EGC are necessary to select appropriate treatment options and promote China's expanded indications for ESD and diagnostic staging scheme. METHODS: This is a multicenter, ambispective, observational, open-cohort study that is expected to enroll 554 patients with EGC. The study was launched in May 2018 and is scheduled to end in March 2022. All enrolled patients should meet the inclusion criteria. Case report forms and electronic data capture systems are used to obtain clinical data, which includes demographic information, results of perioperative blood- and auxiliary examinations, surgical information, results of postoperative pathology, and the outcomes of postoperative recovery and follow-up. Patients are followed up every 6 months after surgery for a minimum of 5 years. The primary endpoint is the rate of lymph node metastasis (LNM), whereas the secondary endpoints include the following: consistency, sensitivity, and specificity of the results of preoperative examinations and postoperative pathology; cut-off values for LNM; logistic regression model of expanded indications for ESD; and incidence of postoperative complications within the 30-day and 5-year relapse-free survival rates. DISCUSSION: This study will explore and evaluate expanded indications for ESD that match the characteristics of the Chinese population in patients with EGC and will introduce a related staging procedure and examination scheme that is appropriate for China. Ethical approval was obtained from all participating centers. The findings are expected to be disseminated through publications or presentations and will facilitate clinical decision-making in EGC. TRIAL REGISTRATION: The name of the registry is ChiCTR. It was registered on May 9, 2018, with the registration number ( ChiCTR1800016084 ). The clinical trial was launched in May 2018 and will end in March 2022, with enrollment to be completed by December 2021. Trial status: Ongoing.

Real-world learning curve analysis of colorectal endoscopic submucosal dissection: a large multicenter study.

BACKGROUND: The current status of colorectal endoscopic submucosal dissection (ESD) performed by endoscopists without colorectal ESD experience is unknown. This study evaluated the quality of colorectal ESD performed by endoscopists without colorectal ESD experience. METHODS: We retrospectively examined the outcomes of 420 consecutive patients with 427 superficial colorectal tumors (male/female, 251/169; mean age, 69 years) who underwent ESD. The procedures were performed by 31 endoscopists without colorectal ESD experience using needle knife-type devices at 13 hospitals from October 2008 to June 2017. Cases were divided into the first and second phases according to the experience of the endoscopist: the first phase included the first 20 cases and the second phase included case 21 and beyond. We also identified factors associated with en bloc resection failure. RESULTS: Rates of colonic tumors, laterally spreading tumors of the non-granular type, poor scope operability, and severe submucosal fibrosis for the first phase were significantly lower than those for the second phase. The en bloc resection rates for the first and second phases were 93% and 96%, respectively. The factors associated with en bloc resection failure were poor scope operability (odds ratio [OR] 2.6; 95% confidence interval [CI] 1.0-6.5), severe submucosal fibrosis (OR 6.5; 95% CI 2.6-15.9), and the first 20 cases (OR 3.4; 95% CI 1.2-10.1). CONCLUSION: Inexperienced endoscopists should initially perform colorectal ESD for tumors without severe submucosal fibrosis under good scope operability for at least 20 cases.

The Mexican consensus on the detection and treatment of early gastric cancer. / Consenso mexicano sobre detección y tratamiento del cáncer gástrico incipiente.

Gastric cancer is one of the most frequent neoplasias in the digestive tract and is the result of premalignant lesion progression in the majority of cases. Opportune detection of those lesions is relevant, given that timely treatment offers the possibility of cure. There is no consensus in Mexico on the early detection of gastric cancer, and therefore, the Asociación Mexicana de Gastroenterología brought together a group of experts and produced the "Mexican consensus on the detection and treatment of early gastric cancer" to establish useful recommendations for the medical community. The Delphi methodology was employed, and 38 recommendations related to early gastric cancer were formulated. The consensus defines early gastric cancer as that which at diagnosis is limited to the mucosa and submucosa, irrespective of lymph node metástasis. In Mexico, as in other parts of the world, factors associated with early gastric cancer include Helicobacter pylori infection, a family history of the disease, smoking, and diet. Chromoendoscopy, magnification endoscopy, and equipment-based image-enhanced endoscopy are recommended for making the diagnosis, and accurate histopathologic diagnosis is invaluable for making therapeutic decisions. The endoscopic treatment of early gastric cancer, whether dissection or resection of the mucosa, should be preferred to surgical management, when similar oncologic cure results can be obtained. Endoscopic surveillance should be individualized.

Feasibility of endoscopic treatment and predictors of lymph node metastasis in early gastric cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) has been routinely performed in applicable early gastric cancer (EGC) patients as an alternative to conventional surgical operations that involve lymph node dissection. The indications for ESD have been recently expanded to include larger, ulcerated, and undifferentiated mucosal lesions, and differentiated lesions with slight submucosal invasion. The risk of lymph node metastasis (LNM) is the most important consideration when deciding on a treatment strategy for EGC. Despite the advantages over surgical procedures, lymph nodes cannot be removed by ESD. In addition, whether patients who meet the expanded indications for ESD can be managed safely remains controversial. AIM: To determine whether the ESD indications are applicable to Chinese patients and to investigate the predictors of LNM in EGC. METHODS: We retrospectively analyzed 12552 patients who underwent surgery for gastric cancer between June 2007 and December 2018 at the Affiliated Hospital of Qingdao University. A total of 1262 (10.1%) EGC patients were eligible for inclusion in this study. Data on the patients' clinical, endoscopic, and histopathological characteristics were collected. The absolute and expanded indications for ESD were validated by regrouping the enrolled patients and determining the positive LNM results in each subgroup. Predictors of LNM in patients were evaluated by univariate and multivariate analyses. RESULTS: LNM was observed in 182 (14.4%) patients. No LNM was detected in the patients who met the absolute indications (0/90). LNM occurred in 4/311 (1.3%) patients who met the expanded indications. According to univariate analysis, LNM was significantly associated with positive tumor marker status, medium (20-30 mm) and large (>30 mm) lesion sizes, excavated macroscopic-type tumors, ulcer presence, submucosal invasion (SM1 and SM2), poor differentiation, lymphovascular invasion (LVI), perineural invasion, and diffuse and mixed Lauren's types. Multivariate analysis demonstrated SM1 invasion (odds ration [OR] = 2.285, P = 0.03), SM2 invasion (OR = 3.230, P < 0.001), LVI (OR = 15.702, P < 0.001), mucinous adenocarcinoma (OR = 2.823, P = 0.015), and large lesion size (OR = 1.900, P = 0.006) to be independent risk factors. CONCLUSION: The absolute indications for ESD are reasonable, and the feasibility of expanding the indications for ESD requires further investigation. The predictors of LNM include invasion depth, LVI, mucinous adenocarcinoma, and lesion size.

Colorectal cancer surveillance in inflammatory bowel disease: Practice guidelines and recent developments.

Patients with long-standing inflammatory bowel disease (IBD) involving at least 1/3 of the colon are at increased risk for colorectal cancer (CRC). Advancements in CRC screening and surveillance and improved treatment of IBD has reduced CRC incidence in patients with ulcerative colitis and Crohn's colitis. Most cases of CRC are thought to arise from dysplasia, and recent evidence suggests that the majority of dysplastic lesions in patients with IBD are visible, in part thanks to advancements in high definition colonoscopy and chromoendoscopy. Recent practice guidelines have supported the use of chromoendoscopy with targeted biopsies of visible lesions rather than traditional random biopsies. Endoscopists are encouraged to endoscopically resect visible dysplasia and only recommend surgery when a complete resection is not possible. New technologies such as virtual chromoendoscopy are emerging as potential tools in CRC screening. Patients with IBD at increased risk for developing CRC should undergo surveillance colonoscopy using new approaches and techniques.

Efficacy and safety of endoscopic submucosal dissection for papillary adenocarcinoma-type early gastric cancer.

Endoscopic submucosal dissection (ESD) has increasingly been used to treat early gastric cancer (EGC); however, its efficacy in treating papillary adenocarcinoma-type EGC remains unknown.We sought to identify risk factors for lymph node (LN) metastasis in papillary adenocarcinoma-type EGC and evaluate the clinical outcome after ESD.This study retrospectively reviewed the medical records of patients who were diagnosed with EGC in our hospital from January 2009 to December 2016. In total, 85 patients had papillary adenocarcinoma-type EGC, of whom 52 and 33 underwent surgical treatment and ESD, respectively. This study analyzed the LN metastasis risk factors and clinical outcomes between these 2 groups and with those of an existing ESD indication group.LN metastasis occurred in 13 (25.0%) of 52 patients who underwent surgery. Multivariate analysis indicated that lymphovascular invasion was an independent risk factor (odds ratio: 20.624; 95% confidence interval: 19.628-21.497; P = .001). Of 33 patients who underwent ESD, 21 (63.6%) had an absolute indication and 12 (36.4%) had an expanded indication. All 3 (9.1%) patients with non-curative resection underwent additional surgery. The clinical outcomes were compared to those of 926 patients who underwent ESD of non-papillary adenocarcinoma-type EGC. There were no significant differences in curative resection rate (P = .327), procedure-related complication (P = .853), local recurrence (P = 1.000), or overall survival (P = 1.000).ESD of papillary adenocarcinoma-type EGC showed an acceptable outcome in comparison to an existing ESD indication group. However, these patients exhibit a relatively higher risk of LN metastasis.

A pilot study to assess the safety and usefulness of combined transurethral endoscopic mucosal resection and en-bloc resection for non-muscle invasive bladder cancer.

BACKGROUND: Transurethral resection (TUR) is the standard operation used for non-muscle invasive bladder cancer (NMIBC). Although most solid tumors are principally removed via single block resection without incising the mass, disruption of the lesion is unavoidable in traditional TUR. Furthermore, pathological diagnosis is often difficult due to heat-related denaturation of tissues in TUR. Although transurethral en-bloc resection is useful for judging tumor invasion, it is associated with a prolonged operative duration. We attempted to show the safety and usefulness of combined endoscopic mucosal resection (EMR) and en-bloc resection in NMIBC patients. METHODS: We investigated 39 patients with clinical NMIBC who were treated using our original EMR + en-bloc resection technique, which involved removal of the tumor mass that protruded from the mucosa, using a polypectomy snare similar to that used for EMR. The residual lesion was removed using en-bloc resection. The operative period, duration of hospitalization, and recurrence rates were compared with those of conventional TUR (n = 31). RESULTS: The mean (standard deviation, range) time interval for EMR and total operative duration were 1.6 (1.1, 1-5) min and 18.3 (10.5, 3-48) min, respectively. The total operative duration was comparable to that of TUR (17.3 min, p = 0.691). The mean duration of catheterization in the EMR + en-bloc resection group (4.2 days) was also similar to that in the TUR group (3.7 days; p = 0.285). No severe complications were observed with EMR + en-bloc resection. The pathologists were able to determine tumor invasiveness with considerable certainty in all specimens obtained via the EMR + en-bloc procedure than via TUR, and the difference in the ease of diagnosis was statistically significant (p = 0.016). Recurrence rates were comparable (p = 0.662) between the EMR + en-bloc (15.4%) and TUR groups (19.4%). CONCLUSIONS: Our results demonstrated that the EMR + en-bloc resection technique is feasible, safe, and useful for treating patients with NMIBC. Furthermore, this technique helps provide a more accurate pathological diagnosis.

Comparison of two methods for endoscopic full-thickness resection of gastrointestinal lesions using OTSC.

Background and aims: The aim of this study was to compare and analyze the feasibility and safety of two methods of endoscopic full-thickness resection (EFTR) for the management of challenging epithelial and subepithelial neoplasms that are not amenable to resection techniques.Material and methods: This was a retrospective case series study of patients who underwent one of two methods of EFTR, resection using ESD knives and post-resection closure with OTSC (Group 1), or closure with OTSC and secondary EFTR with snare (Group 2).Results: Of 11 patients, six were in Group 1 and five in Group 2. The mean time of the EFTR procedure was 76.83 ± 34.97 min in Group 1 which is significantly longer than that of Group 2 (p = .0128). The mean time of OSTC closure and length of hospital stay of Group 1 were also longer compared to Group 2, but the difference was not significant. Complete resection (R0) and technical success rates of Group 1 and Group 2 were 83.3% and 100% (p = .338), respectively. VAS scores of Group 1 immediately after the operation and after 24 h are significantly higher than those of Group 2 (p = .047 and p = .009, respectively). In Group 1, one patient had delayed perforation which led to fever and pneumoperitoneum, and one patient developed abdominal pain. No complications associated with the endoscopic procedure were observed in Group 2.Conclusion: EFTR of pre-resection closure are potentially faster compared with the concept of applying closure after EFTR. Larger prospective controlled studies comparing these two techniques are warranted in the future.

Incidental diagnosis of very small rectal neuroendocrine neoplasms: when should endoscopic submucosal dissection be performed? A single ENETS centre experience.

PURPOSE: The management of small (≤5 mm) rectal neuroendocrine neoplasms (r-NENs), incidentally removed during colonoscopy, still remains under debate. METHODS: All consecutive patients affected by r-NENs from January 2013 to December 2017 were studied. The inclusion criteria were: (1) patients having an incidental pathological diagnosis of very small (≤5 mm) polypoid r-NENs; (2) patients treated with a standard polypectomy as first-line therapy and (3) patients treated by endoscopic submucosal dissection (ESD) as salvage therapy. The primary endpoint was to identify the factors related to residual disease after a standard polypectomy. The secondary endpoint was to calculate the accuracy of endoscopic ultrasound (EUS), grading and size in predicting residual disease. RESULTS: Starting from a prospective database of 123 consecutive patients affected by r-NENs, only 31 met the inclusion criteria. A final pathological examination of an ESD specimen showed residual disease in 7 out of 31 patients (22.6%). A multivariate analysis showed that the size of the polyps was the only independent factor related to residual disease with an odds ratio of 8.7 ± 7.5 (P = 0.013) for each millimetre. The accuracy of EUS, grading and tumour size (3.1 mm cut-off point) and area under the curves were 0.661 ± 0.111, 0.631 ± 0.109 and 0.821 ± 0.109, respectively. CONCLUSIONS: When the r-NEN polyp was larger than 3 mm, ESD was indicated. Unlike the size of the tumour, grading and EUS features did not accurately predict residual disease.

Consensus on the digestive endoscopic tunnel technique.

With the digestive endoscopic tunnel technique (DETT), many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and muscularis propria (MP). Through the tunnel, endoscopic diagnosis or treatment is performed for lesions in the mucosa, in the MP, and even outside the gastrointestinal (GI) tract. At present, the tunnel technique application range covers the following: (1) Treatment of lesions originating from the mucosal layer, e.g., endoscopic submucosal tunnel dissection for oesophageal large or circular early-stage cancer or precancerosis; (2) treatment of lesions from the MP layer, per-oral endoscopic myotomy, submucosal tunnelling endoscopic resection, etc.; and (3) diagnosis and treatment of lesions outside the GI tract, such as resection of lymph nodes and benign tumour excision in the mediastinum or abdominal cavity. With the increasing number of DETTs performed worldwide, endoscopic tunnel therapeutics, which is based on DETT, has been gradually developed and optimized. However, there is not yet an expert consensus on DETT to regulate its indications, contraindications, surgical procedure, and postoperative treatment. The International DETT Alliance signed up this consensus to standardize the procedures of DETT. In this consensus, we describe the definition, mechanism, and significance of DETT, prevention of infection and concepts of DETT-associated complications, methods to establish a submucosal tunnel, and application of DETT for lesions in the mucosa, in the MP and outside the GI tract (indications and contraindications, procedures, pre- and postoperative treatments, effectiveness, complications and treatments, and a comparison between DETT and other operations).

Effect of Continued Administration of Low-dose Aspirin for Intraoperative Bleeding Control in Gastric Endoscopic Submucosal Dissection.

BACKGROUND: The use of antithrombotic agents for the prevention of cerebro-cardioembolic events has increased, and recent guidelines have recommended the continued administration of low-dose aspirin (LDA) during endoscopic procedures with a high risk of bleeding. However, the influence of LDA on intraoperative bleeding control status during Endoscopic submucosal dissection (ESD) remains unclear. METHODS: We examined 293 consecutive patients who underwent ESD for gastric cancers between January 2014 and February 2018. Patients administered with LDA (n = 52) were compared with those without antithrombotic therapy (n = 241; control) by propensity-score matching (PSM) concerning outcomes of ESD. RESULTS: PSM analysis yielded 50 matched pairs. Comparison showed similar values for frequency of intraoperative major bleeding: 1 (0-4) times (median [range]) in the LDA group and 0 (0-5) in the control group respectively (p = 0.710). Others (frequency of preventive coagulation, procedure time, decrease of hemoglobin levels, en bloc resection, complete resection) were the same with a few adverse events including perforation (0%), and thromboembolism (0%). Postoperative bleeding rate was 1.9% in LDA group. Multivariate analysis indicated that location U and circumference on the posterior wall were associated with for multiple major intraoperative bleeding. CONCLUSION: The study suggests that gastric ESD can be safely accomplished without cessation of LDA.

Defining competencies for endoscopic submucosal dissection (ESD) for gastric neoplasms.

BACKGROUND: Current methods for teaching and assessing competencies for endoscopic submucosal dissection (ESD) are highly variable, non-systematic, and are inefficient for the learner to acquire adequate skills. The present study aims to define and establish expert consensus regarding competencies required to perform ESD for gastric neoplasms. METHODS: Fourteen ESD experts from 12 institutions in Japan were invited to complete an online survey to rate potential items for their importance in performing ESD proficiently. By using methodology based on the Delphi principles, the results of each round were analyzed and re-sent to the experts until consensus was established. Items were included if ranked 8 out of a 10-point Likert scale, by ≥ 80% of the respondents. RESULTS: A list of 29 potential items was generated through a review of the literature, textbooks, and experience of the steering group members. Ten new items were added through the survey. Consensus was reached after three rounds. Response rate ranged from 93 to 100%. Thirty-four items achieved consensus as important surrogates of competency in performing ESD. CONCLUSIONS: Essential competencies for performing ESD were identified through expert consensus. These competencies can serve as the foundation for structured training and for development of objective assessment tools to evaluate trainee performance in ESD.

[Comparison of the efficacy and safety between endoscopic submucosal dissection and radical surgery for large colorectal laterally spreading tumors larger than 5 cm in diameter].

OBJECTIVE: To compare the safety and efficacy between endoscopic submucosal dissection (ESD) and radical surgery (RS) for the treatment of large colorectal laterally spreading tumors (LST) larger than 50 mm in diameter. 
 Methods: From January 2011 to January 2016, a total of 82 patients were diagnosed as large LST without deep submucosal invasion (T1 SM2, ≥1 000 µm) in the Second Xiangya Hospital of Central South University. Among them, 52 patients were treated by ESD and the other 30 patients were treated by RS [laparoscopic-assisted colectomy (LAC)/open colectomy (OC)]. The clinic data were retrospectively analyzed and the en-bloc resection rate, en-bloc R0 resection rate, local recurrence, complication, procedure time and hospital stay were collected and analyzed.
 Results: The lesion sizes were (5.80±1.20) cm and (5.53±0.69) cm in diameter for ESD and RS groups, respectively (P>0.05). En-bloc resection rates, en-bloc R0 resection rates and recurrence rates showed no significant difference between the ESD group and RS group (P>0.05). Complication rate of the ESD group (7.69%, 4/52) was much lower than that in the RS group (33.33%, 10/30; P<0.01). The ESD group also had a shorter hospital stay and operation time than the RS group (P<0.05).
 Conclusion: ESD appears to be a safe, minimal invasive and effective strategy for treating large LST and it is obviously better than RS in the aspects of hospital stay, operation time and short-term complication.