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

Management of the colonic polyps referred for surgery: an opportunity for improvement

PURPOSE

To examine local practice for non-malignant polyps and to calculate morbidity and mortality associated with bowel resection for this indication.

METHODS

This retrospective cohort study was conducted by reviewing our local gastrointestinal pathology database over a five-year period to identify colonic resections performed for benign polyps. Using search terms "polyp" and "adenoma," 272 cases were identified. Exclusion criteria included: cancer diagnosis, emergency surgeries, multiple resections, and subtotal colectomies for polyposis. 106 patients were included in the study. Primary outcome was perioperative mortality. Secondary outcomes included patient morbidity, characteristics of polyps requiring surgery, and the number of patients referred for a second endoscopic opinion prior to proceeding with surgery.

RESULTS

64 male and 42 female patients with a mean age of 65.3 years (± 8.6 years) underwent colon resection for benign polyps. The mean polyp size was 32.7 mm (± 19.5 mm). 30 patients (28.6%) had polyps equal to or less than 2 cm. Most of the polyps described were sessile (n = 55, 51.9%) and located in the right colon (n = 84, 79.3%). Endoscopic resection was attempted in 31 patients (29.2%), and five cases (4.7%) were referred for a second endoscopic opinion prior to proceeding with surgery. Endoscopists incorrectly felt that polyps were malignant in 62 cases (58.5%). Using Clavien-Dindo classification, most patients had no complications n = 36 (34.0%) or minor complications n = 41 (38.7%). Twelve patients (11.3%) had complications that required antibiotics, blood transfusions, or total parental nutrition. Nine patients (8.5%) required surgical or endoscopic management. Six patients (5.7%) required ICU admission. Mortality rate was 1.9% (n = 2).

CONCLUSION

Surgery for benign colonic polyps is associated with significant morbidity and mortality. These findings reveal a gap in endoscopic management of benign colonic polyps.

Endoscopic submucosal dissection of gastric neoplastic lesions in Western countries: systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) for gastric neoplastic lesions removal is largely performed in Asian countries. Unfortunately, ESD diffusion, particularly for gastric lesion removal, is still limited in Western countries. We performed a systematic review of available data coming from Western centers. The en bloc and the R0 resection rates for all neoplastic lesions, including early gastric cancer (EGC) and dysplasia, were calculated, as well as the curative rate for EGC. Complications and the 1-month mortality rates were computed. A total of 22 studies from Europe (N = 15), Latina America (N = 6), and Canada (N = 1) were retrieved, with 1152 patients and 1210 lesions. The en bloc resection was successful in 96% [95% confidence interval (CI) 93-98] with a significant heterogeneity (I2 = 63.5%; P < 0.0001). The R0 was achieved in 84% (95% CI 79-89; I2 = 79.9%; P < 0.001). The resection rate was curative in 72% out of 340 patients with EGC (95% CI 65-79, I2 = 8%; P = 0.36). Overall, complications occurred in 9.5% of patients, including bleeding (5.8%), perforation (3.4%), and stenosis (0.35%). A total of three (0.26%) patients deceased within 1 month, but none was directly related to the procedure. Lesion recurrence was observed in 38 (3.5%; 95% CI 2.3-4.4) cases, including 21 EGC and 17 dysplasia. In Western countries, the en bloc and the R0 resections were successful in the large majority of cases, whilst the resection was curative in 72% of patients with EGC. The complications rate was acceptably low.

Surveillance and management of colorectal dysplasia and cancer in inflammatory bowel disease: Current practice and future perspectives

Patients with inflammatory bowel disease (IBD) are at increased risk of developing colorectal cancer (CRC). Current guidelines recommend frequent surveillance colonoscopies for patients with at least left-sided ulcerative colitis, or Crohn's disease involving more than 30% of the colon. Surveillance allows for early detection and treatment of colorectal dysplasia and cancer. The first colonoscopy should be performed 8 to 10 years after onset of disease symptoms. European and British guidelines employ a risk-stratification algorithm that assigns patients to surveillance intervals of one, three or five years, whereas American guidelines recommend to perform surveillance every 1 to 3 years based on the (combined) presence of risk factors. Patients with concomitant primary sclerosing cholangitis are at an additionally increased risk, and should undergo annual surveillance starting immediately after the diagnosis. The current practice of surveillance is based on limited evidence, is resource intensive and cannot preclude the occurrence of interval carcinomas. Fortunately, advances in endoscopic techniques for mucosal visualisation, along with better control of inflammation, have resulted in a declining incidence of CRC in patients with IBD. Furthermore, advanced endoscopic resection techniques can be expected to result in a shift from surgical to endoscopic management of dysplastic lesions. In this review, we provide an up-to-date overview of colitis-associated CRC pathophysiology, epidemiology, surveillance practices, and management of dysplasia.

Hybrid endoscopic submucosal dissection (ESD) compared with conventional ESD for colorectal lesions: a systematic review and meta-analysis

BACKGROUND

Hybrid endoscopic submucosal dissection (ESD) is increasingly utilized to overcome the complexity of conventional ESD. This systematic review and meta-analysis evaluated the efficacy and safety of hybrid ESD for treatment of colorectal lesions.

METHODS

Search strategies were developed in accordance with PRISMA guidelines. Pooled proportions were calculated with rates estimated using random effects models. Measured outcomes included en bloc resection, procedure-associated complications, recurrence, and need for surgery. Subgroup analyses were performed to compare effectiveness of conventional versus hybrid ESD.

RESULTS

16 studies (751 patients) were included with a mean (standard deviation [SD]) lesion size of 27.96 (10.55) mm. En bloc resection rate was 81.63 % (95 % confidence interval [CI] 72.07 - 88.44; I2  = 80.89). Complications, recurrences, and need for surgery occurred in 7.74 % (95 %CI 4.78 - 12.31; I2  = 65.84), 4.52 % (95 %CI 1.40 - 13.65; I2  = 76.81), and 3.64 % (95 %CI 1.76 - 7.37; I2  = 15.52), respectively. Mean procedure duration was 48.83 (22.37) minutes. On subgroup analyses comparing outcomes for conventional (n = 1703) versus hybrid ESD (n = 497), procedure duration was significantly shorter for hybrid ESD (mean difference 18.45 minutes; P = 0.003), with lower complication rates (P = 0.04); however, hybrid ESD had lower en bloc resection rates (P < 0.001). There was no difference in rates of recurrence or surgery (P > 0.05).

CONCLUSION

While hybrid ESD was safe and effective for removal of colorectal lesions, with shorter procedure duration, fewer complications, and no difference in recurrence versus conventional ESD, hybrid ESD was associated with a lower en bloc resection rate.

Enlarged folds on endoscopic gastritis as a predictor for submucosal invasion of gastric cancers

BACKGROUND

Accurate diagnosis of the depth of gastric cancer invasion is crucial in clinical practice. The diagnosis of gastric cancer depth is often made using endoscopic characteristics of the tumor and its margins; however, evaluating invasion depth based on endoscopic background gastritis remains unclear.

AIM

To investigate predicting submucosal invasion using the endoscopy-based Kyoto classification of gastritis.

METHODS

Patients with gastric cancer detected on esophagogastroduodenoscopy at Toyoshima Endoscopy Clinic were enrolled. We analyzed the effects of patient and tumor characteristics, including age, sex, body mass index, surveillance endoscopy within 2 years, current Helicobacter pylori infection, the Kyoto classification, and Lauren’s tumor type, on submucosal tumor invasion and curative endoscopic resection. The Kyoto classification included atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness. Atrophy was characterized by non-reddish and low mucosa. Intestinal metaplasia was detected as patchy whitish or grayish-white flat elevations, forming an irregular uneven surface. An enlarged fold referred to a fold width ≥ 5 mm in the greater curvature of the corpus. Nodularity was characterized by goosebump-like multiple nodules in the antrum. Diffuse redness was characterized by uniform reddish non-atrophic mucosa in the greater curvature of the corpus.

RESULTS

A total of 266 gastric cancer patients (mean age, 66.7 years; male sex, 58.6%; mean body mass index, 22.8 kg/m²) were enrolled. Ninety-three patients underwent esophagogastroduodenoscopy for surveillance within 2 years, and 140 had current Helicobacter pylori infection. The mean Kyoto score was 4.54. Fifty-eight cancers were diffuse-type, and 87 cancers had invaded the submucosa. Multivariate analysis revealed that low body mass index (odds ratio 0.88, P = 0.02), no surveillance esophagogastroduodenoscopy within 2 years (odds ratio 0.15, P < 0.001), endoscopic enlarged folds of gastritis (odds ratio 3.39, P = 0.001), and Lauren’s diffuse-type (odds ratio 5.09, P < 0.001) were independently associated with submucosal invasion. Similar results were obtained with curative endoscopic resection. Among cancer patients with enlarged folds, severely enlarged folds (width ≥ 10 mm) were more related to submucosal invasion than mildly enlarged folds (width 5-9 mm, P < 0.001).

CONCLUSION

Enlarged folds of gastritis were associated with submucosal invasion. Endoscopic observation of background gastritis as well as the lesion itself may help diagnose the depth of cancer invasion.

Endoscopic management of colorectal polyps: From benign to malignant polyps

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer related death in the world. The early detection and removal of CRC precursor lesions has been shown to reduce the incidence of CRC and cancer-related mortality. Endoscopic resection has become the first-line treatment for the removal of most precursor benign colorectal lesions and selected malignant polyps. Detailed lesion assessment is the first critical step in the evaluation and management of colorectal polyps. Polyp size, location and both macro- and micro- features provide important information regarding histological grade and endoscopic resectability. Benign polyps and even malignant polyps with superficial submucosal invasion and favorable histological features can be adequately removed endoscopically. When compared to surgery, endoscopic resection is associated with lower morbidity, mortality, and higher patient quality of life. Conversely, malignant polyps with deep submucosal invasion and/or high risk for lymph node metastasis will require surgery. From a practical standpoint, the most appropriate strategy for each patient will need to be individualized, based not only on polyp- and patient-related characteristics, but also on local resources and expertise availability. In this review, we provide a broad overview and present a potential decision tree algorithm for the evaluation and management of colorectal polyps that can be widely adopted into clinical practice.

AGA Clinical Practice Update on Endoscopic Surveillance and Management of Colorectal Dysplasia in Inflammatory Bowel Diseases: Expert Review

Improvements in disease management, as well as endoscopic technology and quality, have dramatically changed the way in which we conceptualize and manage inflammatory bowel disease-related dysplasia over the past 20 years. Based on evolving literature, we propose a conceptual model and best practice advice statements for the prevention, detection, and management of colorectal dysplasia in people with inflammatory bowel disease. This expert review was commissioned and approved by the American Gastroenterological Association Institute Clinical Practice Updates Committee and the American Gastroenterological Association Governing Board to provide timely guidance on a topic of high clinical importance to the American Gastroenterological Association membership. It underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology.

Bleeding after endoscopic resection between direct oral anticoagulants or warfarin: Systematic review and meta-analysis

BACKGROUND AND AIM

Oral anticoagulants are risk factors for post-endoscopic resection bleeding. We aimed to conduct a systematic review and meta-analysis for the risks of post-procedural bleeding (PPB) for direct oral anticoagulants (DOACs) and warfarin following endoscopic resection.

METHODS

Two independent reviewers searched PubMed, Web of Science, Embase, and Cochrane Library. The Newcastle-Ottawa Scale score was used to assess the quality of the studies, the pooled odds ratio (OR) to present PPB results, and the funnel plots to assess publication bias. The Higgins I² statistic was employed to determine the variation across studies due to heterogeneity.

RESULTS

We reviewed 30 articles. PPB occurred in 586 patients on DOACs and 1782 on warfarin. The patients on DOACs had a significantly lower overall risk of PPB compared with those on warfarin (OR, 0.867, 95% confidence interval, 0.771-0.975; P = 0.017, I²  = 1.6%). Cumulative meta-analysis showed that the PPB rate of DOACs has the trend to be lower than that of warfarin with publication year and sample size. For the subgroup of endoscopic submucosal dissection, the PPB of DOACs was significantly lower than that of warfarin (OR, 0.786; 95% confidence interval, 0.633-0.976; P = 0.029, I²  = 0%). No significant difference was observed between DOACs and warfarin for anticoagulant strategies, endoscopic procedures, and lesion location.

CONCLUSIONS

Compared with warfarin, DOACs have the possibility to significantly decrease the risk of PPB following endoscopic resection, especially for endoscopic submucosal dissection.

GIE Editorial Board top 10 topics: advances in GI endoscopy in 2020

The American Society for Gastrointestinal Endoscopy's Gastrointestinal Endoscopy Editorial Board reviewed a systematic literature search of original endoscopy-related articles published during 2020 in Gastrointestinal Endoscopy and 10 other high-impact medical and gastroenterology journals. Votes from each individual board member were tallied to identify a consensus list of the 10 most significant topic areas in GI endoscopy over the calendar year of study using 4 criteria: significance, novelty, impact on national health, and impact on global health. The 10 areas identified were as follows: artificial intelligence in endoscopy, coronavirus disease 2019 and GI practice, third-space endoscopy, lumen-apposing metal stents, single-use duodenoscopes and other disposable equipment, endosonographic needle technology and techniques, endoscopic closure devices, advances in GI bleeding management, improvements in polypectomy techniques, and bariatric endoscopy. Each board member contributed a summary of important articles relevant to 1 to 2 topic areas, leading to a collective summary that is presented in this document of the "top 10" endoscopic advances of 2020.

ENDOSCOPIC SUBMUCOSAL DISSECTION WITH CIRCUMFERENTIAL INCISION VERSUS TUNNELING METHOD FOR TREATMENT OF SUPERFICIAL ESOPHAGEAL CANCER

BACKGROUND

Endoscopic submucosal dissection (ESD) of esophageal superficial neoplasm is associated with a high en bloc R0 resection rate and low recurrence.

OBJECTIVE

We aim to compare the performance and clinical outcomes of ESD via ESD after circumferential incision (ESD-C) versus submucosal tunneling (ESD-T).

METHODS

Single-center retrospective analysis of all consecutive patients who underwent ESD for superficial esophageal cancer, between 2009 and 2018. ESD-T was defined as the technique of making the mucosal incisions followed by submucosal tunneling in the oral to anal direction. ESD-C consisted of completing a circumferential incision followed by ESD. Main study outcomes included en bloc and R0 resection rates. Secondary outcomes included procedural characteristics, curative resection rate, local recurrence and adverse events.

RESULTS

A total of 65 procedures (23 ESD-T and 42 ESD-C) were performed for ESCC (40; 61.5%) and BE-neoplasia (25; 38.5%). There were no statistically significant differences between patients who underwent ESD-T versus ESD-C in en bloc (91.3% vs 100%, P=0.12), R0 (65.2% vs 78.6%, P=0.24), curative resection rates (65.2% vs 73.8%, P=0.47) and mean procedure time (118.7 min with vs 102.4 min, P=0.35). Adverse events for ESD-T and ESD-C were as follows: bleeding (0 versus 2.4%; P=0.53), perforation (4.3% vs 0; P=0.61), esophageal stricture (8.7% versus 9.5%; P=0.31). Local recurrence was encountered in 8.7% after ESD-T and 2.4% after ESD-C (P=0.28) at a mean follow-up of 8 and 2.75 years, respectively (P=0.001).

CONCLUSION

ESD-T and ESD-C appear to be equally effective with similar safety profiles for the management of superficial esophageal neoplasms.

Colorectal Endoscopic Submucosal Dissection: An Update on Best Practice

Endoscopic submucosal dissection (ESD) is a method of en-bloc resection of neoplastic colorectal lesions which is less invasive compared to surgical resection. Lesion stratification, architecture recognition and estimation of depth of invasion are crucial for patient selection. Expert endoscopists have integrated a variety of classification systems including Paris, lateral spreading tumor (LST), narrow band imaging (NBI), international colorectal endoscopic (NICE) and Japanese NBI expert team (JNET) in their day-to-day practice to enhance lesion detection accuracy. Major societies recommend ESD for LST-non granular (NG), Kudo-VI type, large depressed and protruded colonic lesions with shallow submucosal invasion. Chance of submucosal invasion enhances with increased depth as well as tumor location and size. In comparison to endoscopic mucosal resection (EMR), ESD has a lowerl recurrence rate and higher curative resection rate, making it superior for larger colonic lesions management. Major complications such as bleeding and perforation could be seen in up to 11% and 16% of patients, respectively. In major Western countries, performing ESD is challenging due to limited number of expert providers, lack of insurance coverage, and unique patient characteristics such as higher BMI and higher percentage of previously manipulated lesions.

Efficacy of Endoscopic Submucosal Dissection for Superficial Gastric Neoplasia in a Large Cohort in North America

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is a widely accepted treatment option for superficial gastric neoplasia in Asia, but there are few data on outcomes of gastric ESD from North America. We aimed to evaluate the safety and efficacy of gastric ESD in North America.

METHODS

We analyzed data from 347 patients who underwent gastric ESD at 25 centers, from 2010 through 2019. We collected data on patient demographics, lesion characteristics, procedure details and related adverse events, treatment outcomes, local recurrence, and vital status at the last follow up. For the 277 patients with available follow-up data, the median interval between initial ESD and last clinical or endoscopic evaluation was 364 days. The primary endpoint was the rate of en bloc and R0 resection. Secondary outcomes included curative resection, rates of adverse events and recurrence, and gastric cancer-related death.

RESULTS

Ninety patients (26%) had low-grade adenomas or dysplasia, 82 patients (24%) had high-grade dysplasia, 139 patients (40%) had early gastric cancer, and 36 patients (10%) had neuroendocrine tumors. Proportions of en bloc and R0 resection for all lesions were 92%/82%, for early gastric cancers were 94%/75%, for adenomas and low-grade dysplasia were 93%/ 92%, for high-grade dysplasia were 89%/ 87%, and for neuroendocrine tumors were 92%/75%. Intraprocedural perforation occurred in 6.6% of patients; 82% of these were treated successfully with endoscopic therapy. Delayed bleeding occurred in 2.6% of patients. No delayed perforation or procedure-related deaths were observed. There were local recurrences in 3.9% of cases; all occurred after non-curative ESD resection. Metachronous lesions were identified in 14 patients (6.9%). One of 277 patients with clinical follow up died of metachronous gastric cancer that occurred 2.5 years after the initial ESD.

CONCLUSIONS

ESD is a highly effective treatment for superficial gastric neoplasia and should be considered as a viable option for patients in North America. The risk of local recurrence is low and occurs exclusively after non-curative resection. Careful endoscopic surveillance is necessary to identify and treat metachronous lesions.

Practice pattern variability among gastroenterologists in colorectal cancer surveillance and management of colorectal dysplasia in inflammatory bowel disease

OBJECTIVE

There is debate on the best method of colorectal cancer (CRC) surveillance in inflammatory bowel disease (IBD). We aimed to examine how gastroenterologists around the world practice CRC surveillance and manage dysplastic lesions in IBD.

METHODS

A 22-question survey was emailed to gastroenterologists from 34 countries. It included questions on resources for, frequency and mode of CRC surveillance, and management of colorectal dysplasia. Fisher's exact test and logistic regression were used to evaluate the differences among respondents in various domains.

RESULTS

There were 217 eligible responses, with most gastroenterologists working in public hospitals (76%), and treating >10 patients with IBD weekly (71%). High-definition white light endoscopy (HDWLE) was available in 93.1% of the centers. The preferred mode of surveillance was HDWLE with dye-spray chromoendoscopy and targeted biopsies (41.2%). Fewer than 50% of physicians reported using chromoendoscopy in >50% of cases, citing time as the limiting factor (73.7%). Of these gastroenterologists 63% infrequently (<25% of cases) performed random biopsies during chromoendoscopy. They would attempt endoscopic mucosal resection for polypoid lesions >10 mm (67.2%), including >20 mm lesions with low grade dysplasia (49.8%), and non-polypoid lesions >10 mm without dysplasia (56.9%). For non-polypoid lesions >20 mm with low- and high-grade dysplasia, referral to expert endoscopists was the preferred option.

CONCLUSION

The preferred method of CRC surveillance was HDWLE with chromoendoscopy and targeted biopsies. Random biopsies were infrequently performed. The uptake of chromoendoscopy for surveillance in practice was low. Physicians varied in their approach in removing endoscopically resectable dysplastic lesions.

Recent advances in early esophageal cancer: diagnosis and treatment based on endoscopy

Esophageal cancer (EC) often cannot be discovered in time because of its asymptomatic or symptom-atypical characteristics in early stage. The risk and probability of lymph node metastasis and distant metastasis increase correspondingly as the cancer aggressively invades deeper layers. Treatment regimens may be shifted to surgery and chemoradiotherapy (CRT) from endoscopic eradication therapy (EET) with poor quality of life and prognosis. It is imperative to identify dysplasia and EC early and enable early curative endoscopic treatments. Newer methods have been attempted in the clinical setting to achieve early detection at a more microscopic and precise level. Newer imaging techniques and artificial intelligence (AI) technology have been involved in targeted biopsies and will gradually unveil the visualization of pathology in the future. Early detection and diagnosis are the prerequisite to choose personal and precise treatment regimens. EET has also been undergoing development and improvement to benefit more patients as the first option or the firstly chosen alternative therapy, when compared with esophagectomy. More clinical studies are needed to provide more possibilities for EET.

Tip-in Endoscopic Mucosal Resection for 15- to 25-mm Colorectal Adenomas: A Single-Center, Randomized Controlled Trial (STAR Trial)

INTRODUCTION

One-piece endoscopic mucosal resection (EMR) for lesions >15 mm is still unsatisfactory, and attempted 1-piece EMR for lesions >25 mm can increase perforation risk. Therefore, modifications to ensure 1-piece EMR of 15- to 25-mm lesions would be beneficial. The aim of this study was to investigate whether Tip-in EMR, which anchors the snare tip within the submucosal layer, increases en bloc resection for 15- to 25-mm colorectal lesions compared with EMR.

METHODS

In this prospective randomized controlled trial, patients with nonpolypoid colorectal neoplasms of 15-25 mm in size were recruited and randomly assigned in a 1:1 ratio to undergo Tip-in EMR or standard EMR, stratified by age, sex, tumor size category, and tumor location. The primary endpoint was the odds ratio of en bloc resection adjusted by location and size category. Adverse events and procedure time were also evaluated.

RESULTS

We analyzed 41 lesions in the Tip-in EMR group and 41 lesions in the EMR group. En bloc resection was achieved in 37 (90.2%) patients undergoing Tip-in EMR and 30 (73.1%) who had EMR. The adjusted odds ratio of en bloc resection in Tip-in EMR vs EMR was 3.46 (95% confidence interval: 1.06-13.6, P = 0.040). The Tip-in EMR and EMR groups did not differ significantly in adverse event rates (0% vs 4.8%) or median procedure times (7 vs 5 minutes).

DISCUSSION

In this single-center randomized controlled trial, we found that Tip-in EMR significantly improved the en bloc resection rate for nonpolypoid lesions 15-25 mm in size, with no increase in adverse events or procedure time.

Endoscopic Resection of Gastric Cancer

With improvements in the early detection of early gastric cancer (EGC) and advances in therapeutic techniques, endoscopic resection (ER) for EGC has become widely adopted in East Asian and Western countries. Endoscopic submucosal dissection has higher rates of en bloc, complete, and curative resections with lower rates of local recurrence than that of endoscopic mucosal resection. ER is a minimally invasive method with low morbidity that provides excellent outcomes. ER for EGC is a safe, effective method, preserving organ function and thus maintaining the patient's quality of life, and is recognized as the first-line treatment of EGC in selected patients.

Chitosan thermosensitive hydrogels based on lyophilizate powders demonstrate significant potential for clinical use in endoscopic submucosal dissection procedures

The goal of this study was to develop intraoperative biomaterials for use in endoscopic submucosal dissection (ESD) procedures that are stable during storage, easy to use, and effective in clinical practice. Therefore, injectable thermosensitive hydrogels were developed based on lactobionic acid-modified chitosan/chitosan/β-glycerophosphate (CSLA/CS/GP) hydrogel lyophilizate powders, and their properties were compared with original hydrogels that had not been freeze-dried. The results indicated that the lyophilizate powders retained their thermosensitive properties, and gels could be formed within 5 min at 37 °C. Compared to the original hydrogels, the injectability of the hydrogels derived from lyophilizate powders increased significantly. These novel materials maintained their original porous network lamellar structure but exhibited improved mechanical strength and tissue adhesion. Their application with L929 and GES-1 cells revealed that the lyophilizate powder hydrogels demonstrated good cytocompatibility and clearly protected the cells in an acidic environment. The results of submucosal injection experiments involving porcine stomach tissue indicated that the heights of the cushions created by CSLA/CS/GP lyophilizate powder hydrogels lasted longer than those generated with normal saline. The thermosensitive hydrogels based on lyophilizate powders may contribute to practical clinical applications involving ESD, and may also have potential value for other applications in the digestive tract.

Prevention and Management of Complications and Education in Endoscopic Submucosal Dissection

Endoscopic submucosal dissection (ESD) is considered superior to endoscopic mucosal resection as an endoscopic resection because of its higher en bloc resection rate, but it is more difficult to perform. As ESD techniques have become more common, and the range of treatment by ESD has expanded, the number of possible complications has also increased, and endoscopists need to manage them. In this report, we will review the management of critical complications, such as hemorrhage, perforation, and stenosis, and we will also discuss educational methods for acquiring and improving ESD skills.

Optimal procedure-related hospitalization using clinical pathway protocols following gastric endoscopic submucosal dissection

BACKGROUND

The clinical pathway (CP) protocols simplified a systematic process from hospitalization to discharge, and were conducted to achieve standardization of the treatment process as well as improve outcomes. Thus, we investigated the optimal procedure-related hospitalization period following gastric endoscopic submucosal dissection (ESD) by comparing the rate of delayed bleeding (DB) and perforation according to CP protocols.

METHODS

We retrospectively enrolled 630 patients who underwent ESD for gastric dysplasia or early gastric cancer (EGC); Group A (368 patients) followed Protocol A for a hospital stay of a single night; Group B (262 patients) followed Protocol B for a hospital stay of two nights.

RESULTS

The patient characteristics were comparable between the two groups, except for pathologic diagnosis (42.1% in Group A vs. 32.1% in Group B for EGC). DB occurred in 21 patients, and there was no significant difference in the overall DB rates between Group A (12/368 = 3.3%) and Group B (9/262 = 3.4%) (P = 0.904). The DB rates were 2.5% (8/315) and 7.5% (4/53) in Group A, and 2.7% (6/223) and 7.7% (3/39) in Group B, without and with the use of antiplatelets, respectively, and 33.3% (1/3) in Group A and 50.0% (1/2) in Group B with the use of dual antiplatelets. DB developed at various intervals post-discharge from 2 to 17 days, and was successfully controlled by endoscopic hemostasis in most cases. There were no deaths or surgeries required as a result of uncontrolled DB and no postoperative delayed perforation occurred.

CONCLUSIONS

The CP protocols with a one-night hospitalization following gastric ESD decreased the hospital stay and did not influence postoperative complications compared to those with two-night hospitalizations.

Incidence rates, risk factors, and outcomes of aspiration pneumonia after gastric endoscopic submucosal dissection: A systematic review and meta-analysis

BACKGROUND AND AIM

The risk and prognosis of aspiration pneumonia (AP) after endoscopic submucosal dissection (ESD) are inconsistent among studies. We aim to estimate the incidence, risk factors, and outcome of AP in patients after gastric ESD.

METHODS

PubMed, EMBASE, Cochrane Library, and Web of Knowledge were searched for relevant articles from inception until April 2020. Data involving the incidence, risk factors, and outcomes were extracted. Pooled incidence, odds ratios (ORs), or standardized mean difference (SMD) and 95% confidence intervals (CIs) were calculated.

RESULTS

Forty records involving 48 674 subjects were finally included. The pooled incidence of AP after gastric ESD was 1.9% (95% CI, 1.2-2.7) via the double arcsine transformation method and 1.6% (1.1-2.5%) via the logit transformation method. Risk factors analyses revealed that old age (OR, 2.52; 95% CI, 1.99-3.18), comorbid pulmonary disease (2.49; 1.66-3.74), comorbid cerebrovascular disease (2.68; 1.05-6.85), remnant stomach (4.91; 1.83-13.14), sedation with propofol (2.51; 1.48-4.28), and long procedural duration (count data: 5.20, 1.25-21.7; measurement data: 1.01, 1.01-1.02) were related to the occurrence of AP. Patients with AP had a longer hospital stay (SMD, 0.56; 95% CI, 0.25-0.87) than those without AP.

CONCLUSIONS

About 1.9% (1.2-2.7%) of the patients who receive gastric ESD may develop AP, resulting in prolonged hospital stay. More attention should be paid in patients who are older; have comorbidities such as pulmonary diseases, cerebrovascular diseases, or gastric remnant; or require a long procedural duration or deep sedation with propofol.

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.

An evaluation of resectability among endoscopic treatment methods for rectal neuroendocrine tumors <10 mm

BACKGROUND AND STUDY AIMS

With respect to rectal neuroendocrine tumor (NET) resection, it remains unclear which of the following methods is the most effective: conventional endoscopic mucosal resection (cEMR), EMR using a fitted cap (EMR-C), EMR with a ligation band device (EMR-L), or endoscopic submucosal dissection (ESD). Thus, in this study, we aim to retrospectively evaluate the most effective endoscopic resection for rectal NETs < 10 mm.

PATIENTS AND METHODS

In total, 61 consecutive patients with primary rectal NETs < 10 mm in diameter were included in this study; they were then divided into three groups: those with cEMR; those with modified EMR (mEMR) involving EMR-C and EMR-L; and those with ESD. The primary endpoint was to evaluate the difference in the complete en bloc resection rate. The secondary endpoint was to investigate differences in procedure time and complications.

RESULTS

Among the three groups, a significant difference was found in procedure time (cEMR vs ESD, P < .01; mEMR vs ESD, P < .01), en bloc resection rate (cEMR vs mEMR, P = .015), tumor size (mEMR vs ESD, P < .01), percentage of tumor diameter ≥ 5 mm (mEMR vs ESD, P < .01), and complete en bloc resection rate (cEMR vs mEMR, P = .014). Meanwhile, no significant difference was noted in terms of complication rate among the three groups.

CONCLUSION

The mEMR was the most suitable resection method for rectal NETs < 10 mm with respect to the risks and benefits from procedure-related factors, such as complete en bloc resection rate, procedure time, and complication rate.

Injectable Thermogel Generated by the "Block Blend" Strategy as a Biomaterial for Endoscopic Submucosal Dissection

Endoscopic submucosal dissection is an established method for the removal of early cancers and large lesions from the gastrointestinal tract but is faced with the risk of perforation. To decrease this risk, a submucosal fluid cushion (SFC) is needed clinically by submucosal injection of saline and so on to lift and separate the lesion from the muscular layer. Some materials have been tried as the SFC so far with disadvantages. Here, we proposed a thermogel generated by the "block blend" strategy as an SFC. This system was composed of two amphiphilic block copolymers in water, so it was called a "block blend". We synthesized two non-thermogellable copolymers poly(d,l-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(d,l-lactide-co-glycolide) and blended them in water to achieve a sol-gel transition upon heating in both pure water and physiological saline. We explored the internal structure of the resultant thermogel with transmission electron microscopy, three-dimensional light scattering, ¹³C NMR, fluorescence resonance energy transfer, and rheological measurements, which indicated a percolated micelle network. The biosafety of the synthesized copolymer was preliminarily confirmed in vitro. The main necessary functions as an SFC, namely, injectability of a sol and the maintained mucosal elevation as a gel after injection, were verified ex vivo. This study has revealed the internal structure of the block blend thermogel and illustrated its potential application as a biomaterial. This work might be stimulating for investigations and applications of intelligent materials with both injectability and thermogellability of tunable phase-transition temperatures.

Outcomes of 601 Colorectal Endoscopic Submucosal Dissections in a Single Western Center: Is Right Colon Location Still a Major Concern?

BACKGROUND

Endoscopic submucosal dissection (ESD), as a minimally invasive procedure for removal of early gastrointestinal neoplasms, is a standard approach in Asian countries. Outcomes of ESD in Western European countries significantly differ, which makes it more difficult to apply this procedure to daily-basis clinical routine. The aim of this study is to analyze the safety and efficiency of colorectal ESD based on a large series of cases performed by a single operator after finishing the learning curve period in a western referral center.

MATERIALS AND METHODS

We retrospectively studied 601 patients who underwent ESD procedure for colorectal neoplasm from January 2016 to December 2019 in a tertiary colorectal ESD center in Poland.

RESULTS

The overall en bloc resection was achieved in 88.02%. Complete histologic resection rate (R0) was reported at a level of 86.36%. Lesions located in the right colon were characterized by statistically lower en bloc, R0 resection, and success rate (73.95%, 71.43%, 69.75%, respectively). In 9.82% (n=59) of cases, the ESD procedure-related complications have been observed. Post-ESD bleeding occurred in 23 patients (3.83%) and perforation in 32 patients (5.32%). Twenty-seven patients were treated endoscopically (4.49%) and 5 required surgery (0.83%). Analysis of complications showed that tumors located within the right colon were characterized by the highest perforation rate at 10.92%. Within the rectum there were minimal number of perforations (2.69%), whereas the bleeding rate was 4.48%.

CONCLUSIONS

Our results represent the largest material concerning ESD of colorectal lesions in the West and show that ESD is characterized by a high rate of successful resections with a low risk of complications. Thus, confirming that it is possible to obtain results similar to Asian centers and that colorectal ESD procedures can be implemented in clinical routine in western countries. Nevertheless, ESD in the right colon is still related with high rate of complications, so qualification for the ESD procedure should be very careful and discussed with the patient and should be performed by an experienced endoscopist after the learning curve.

Close Observation versus Additional Surgery after Noncurative Endoscopic Resection of Esophageal Squamous Cell Carcinoma

INTRODUCTION

After noncurative endoscopic submucosal dissection (ESD) of superficial esophageal squamous cell carcinoma (SESCC), additional esophagectomy is generally recommended. However, considering its high mortality and morbidity, it is uncertain if additional surgery improves the clinical outcomes. This study aimed to compare the clinical outcomes between patients who were observed without additional treatment and those who underwent radical esophagectomy.

METHODS

A total of 52 patients with SESCC who underwent complete but noncurative ESD from January 2008 to December 2016 at the Samsung Medical Center and Asan Medical Center in Korea were retrospectively analyzed. Clinicopathologic characteristics and oncologic outcomes were compared between the observation group (n = 23) and the additional surgery group (n = 29).

RESULTS

During a mean follow-up of 34.4 and 41.7 months, respectively, the rates of death (observation vs. surgery, 17.4 vs. 10.3%; p = 0.686), recurrence (observation vs. surgery, 13 vs. 17.2%; p = 1.000), and disease-specific death (observation vs. surgery, 4.3 vs. 6.9%; p = 1.000) did not significantly differ between the 2 groups. The 3-year overall survival was 86.3 and 96.4%, respectively (p = 0.776). The 3-year recurrence-free survival (observation vs. surgery, 85.0 vs. 88.7%; p = 0.960) and disease-specific survival (observation vs. surgery, 95.2 vs. 96.4%; p = 0.564) also did not significantly differ.

CONCLUSIONS

The clinical outcomes of close observation of noncuratively resected SESCC are comparable to those of additional surgery, at least in the midterm. The wait-and-see strategy could be a feasible management option after noncurative ESD of SESCC in selected patients.

Efficacy and safety of endoscopic submucosal dissection versus endoscopic mucosal resection for superficial esophageal carcinoma: a systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) has been developed to overcome the limitations of endoscopic mucosal resection (EMR). Yet, the potential for EMR should not be ignored. This study aimed to compare the efficacy and safety of ESD and EMR in the treatment of superficial esophageal carcinoma (SEC). All relevant articles were retrieved from electronic databases. The primary outcomes included en bloc resection, curative resection, R0 resection, and local recurrence rates. Secondary outcomes included procedure time, rates of perforation, bleeding, and postoperative stricture. Subgroup analyses based on histologic types and lesion sizes were conducted. Twenty-two studies were enrolled. Overall results showed higher en bloc, curative, and R0 resection rate, and lower recurrence rate in ESD compared with EMR. ESD was significantly more time-consuming and induced more perforations than EMR procedure. In subgroup analyses of squamous cell carcinoma (SCC) and Barrett's esophagus (BE)-associated neoplasia and esophageal adenocarcinoma (EAC) subtypes, ESD also excelled in en bloc, curative, R0 resection and local recurrence rates. However, in subgroup analysis stratifying outcomes according to lesion sizes, the superior effect of ESD in en bloc resection, curative resection, and local recurrence rate only manifested when lesion size >20 mm. Overall, ESD seemed to have superior efficacy and similar safety profiles compared to EMR in treating SCC, BE-associated neoplasia and EAC. Nevertheless, the selection of ESD or EMR should take lesion size into consideration. EMR is appropriate when lesion size ≤10 mm, EMR and ESD are both applicable for lesion between 11 and 20 mm, and ESD is preferable for lesions >20 mm. More evidences are needed to confirm the current findings.

A Review of Endoscopic Full-thickness Resection, Submucosal Tunneling Endoscopic Resection, and Endoscopic Submucosal Dissection for Resection of Subepithelial Lesions

Gastrointestinal subepithelial tumors (SETs) are often found while performing routine endoscopy. Recently, there has been the development of new endoscopic techniques such as endoscopic submucosal dissection, submucosal tunnel endoscopic resection, and endoscopic full-thickness resection, all minimally invasive approaches which have made it possible to resect SETs that were previously resected with surgery. This review discusses the endoscopic treatment of patients with SETs, outcomes for endoscopic treatment, procedure-related complications, and advantages and disadvantages of these endoscopic techniques.

The who, what, where, how, and why of endoscopic submucosal dissection in Canada: A survey among Canadian endoscopists

Background and Aim

Endoscopic submucosal dissection (ESD) is an internationally accepted technique for the resection of superficial gastrointestinal neoplasia. ESD allows for en-bloc removal when endoscopic mucosal resection (EMR) is unsuitable due to the size or depth of the lesion. The aim of this survey was to examine Canadian clinicians' experience and perceptions of ESD as its prevalence increases across the country.

Methods

An electronic survey consisting of 24 multiple-choice questions was distributed via the Canadian Association of Gastroenterology email database and directly to those known to be performing or interested in ESD. The survey covered training, practice, obstacles in implementation, and perceptions of the future of ESD in Canada.

Results

A total of 21 participants completed the survey. ESD was performed primarily in the endoscopy suite exclusively (71%), and most operators (64%) performed it on an outpatient basis. Procedure time was selected as the greatest technical challenge in the performance of ESD by 86% of the participants. Both lack of formalized training and long procedure times were the highest ranked barriers to the adoption of ESD. Over the next 5 years, 95% believed there would be an increase in ESD volume in Canada, and 43% believed ESD was ready for adoption by more therapeutic endoscopists.

Interpretation

In this survey, we explored the current practice, attitude, and challenges of ESD in the Canadian landscape. As the performance of ESD increases and gains more acceptance across Canada, there are opportunities to address technical challenges and barriers through the formalization of training, education, and practice guidelines.

Appropriate endoscopic treatment selection and surveillance for superficial non-ampullary duodenal epithelial tumors

OBJECTIVES

Superficial nonampullary duodenal epithelial tumors (SNADETs) have become frequently detected and referred for endoscopic resection (ER). However, optimal treatment methods and long-term outcomes after ER of SNADETs have not been fully elucidated. We aimed to clarify them by analyzing our large cohort of patients with SNADETs.

MATERIALS AND METHODS

We enrolled 190 consecutive tumors from 189 patients undergoing ER between January 2004 and September 2019. Cases were stratified into endoscopic submucosal dissection (ESD), conventional endoscopic mucosal resection, (CEMR) and underwater endoscopic mucosal resection (UEMR). Baseline characteristics and short-term outcomes were compared between the groups. Long-term outcomes were also investigated with a median follow-up of 36 months.

RESULTS

ESD significantly exceeded CEMR (96.4% vs. 52.9%; p = .0026) and UEMR (96.4% vs. 50.0%; p = .0008) in complete resection rates for 11- to 20-mm lesions; the differences were not significant for lesions ≤10 mm. Local recurrence only occurred in patients with an incomplete resection. Only patients with submucosal invasion died from the primary neoplasms. The 3- and 5-year disease-free survivals were 91.3% and 83.5%.

CONCLUSIONS

While tumors ≤10 mm seem to be good indications for endoscopic mucosal resection, ESD should be considered for larger tumors to better achieve complete resection. Patients with submucosal invasive carcinomas have a great risk of cancer death. Therefore, a close follow-up and an additional treatment are desirable.

Quality in diagnostic upper gastrointestinal endoscopy for the detection and surveillance of gastric cancer precursor lesions: Position paper of AEG, SEED and SEAP

This position paper, sponsored by the Asociación Española de Gastroenterología [Spanish Association of Gastroenterology], the Sociedad Española de Endoscopia Digestiva [Spanish Gastrointestinal Endoscopy Society] and the Sociedad Española de Anatomía Patológica [Spanish Anatomical Pathology Society], aims to establish recommendations for performing an high quality upper gastrointestinal endoscopy for the screening of gastric cancer precursor lesions (GCPL) in low-incidence populations, such as the Spanish population. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates different measures to improve the quality of upper gastrointestinal endoscopy in this setting and makes recommendations on how to evaluate and treat the identified lesions. We recommend that upper gastrointestinal endoscopy for surveillance of GCPL should be performed by endoscopists with adequate training, administering oral premedication and use of sedation. To improve the identification of GCPL, we recommend the use of high definition endoscopes and conventional or digital chromoendoscopy and, for biopsies, NBI should be used to target the most suspicious areas of intestinal metaplasia. Regarding the evaluation of visible lesions, the risk of submucosal invasion should be evaluated with magnifying endoscopes and endoscopic ultrasound should be reserved for those with suspected deep invasion. In lesions amenable to endoscopic resection, submucosal endoscopic dissection is considered the technique of choice.

An innovative next-generation endoscopic submucosal injection material with a 2-step injection system (with video)

BACKGROUND AND AIMS

Next-generation submucosal injection materials (SIMs) with higher performance and flexibility than the current SIMs (eg, 0.4% sodium hyaluronate solution [HA]) are expected to improve the outcomes of endoscopic submucosal dissection (ESD) but are difficult to develop. We developed a next-generation SIM by devising a 2-solution-type SIM comprising 2.0% calcium chloride solution (Ca) and 0.4% sodium alginate solution (SA) and evaluated its performance.

METHODS

Viscoelasticity, submucosal elevation height, and injection pressure of HA, SA, and the next-generation SIM were measured. Outcomes of ESDs on pseudo-lesions in ex vivo porcine stomach/colon models were compared.

RESULTS

The dramatic increase in SA viscoelasticity with the addition of Ca facilitated the formation of highly viscous submucosal cushions that can be controlled by endoscopists. The submucosal elevation height of the next-generation SIM was significantly higher than that of HA or SA with the same injection pressure. The ESD procedure time using the next-generation SIM was significantly shorter than that using HA or SA (14.2 ± 6.1 vs 29.2 ± 9.1 minutes, P = .0004, or 14.2 ± 6.1 vs 29.1 ± 5.9 minutes, P <.0001). Furthermore, the total injection volume for the next-generation SIM was considerably lower than that for HA or SA (7.0 ± 0.9 vs 17.2 ± 3.4 mL, P <.0001, or 7.0 ± 0.9 vs 16.2 ± 2.9 mL, P <.0001).

CONCLUSIONS

We developed an ideal next-generation SIM that achieved high performance and high flexibility in ex vivo models. Our findings warrant further investigations in a patient population.

Long-term Outcomes and Factors Affecting the Survival of Patients with Mucosal Esophageal Squamous Cell Carcinoma

Background/Aims

Data regarding the prognosis of early esophageal cancer are lacking. This study investigated the long-term outcomes and factors affecting the survival of patients with mucosal esophageal squamous cell carcinoma (T1aESCC).

Methods

We analyzed the clinical and tumor-specific parameters of 263 patients who received surgical resection (SR; n=63) or endoscopic resection (ER; n=200) for T1aESCC. Underlying comorbidities were scored using the Charlson Comorbidity Index (CCI). Overall survival (OS) was the primary outcome, and multivariate regression analysis was performed to predict factors for OS.

Results

Of the study patients (age, 64.5±8.0 years), the CCI was 1.0±1.4 in the ER group and 0.6±0.9 in the SR group (p=0.107). The 5-year OS rate during follow-up (54.4±20.4 months) was 85.7% (ER group, 86.8%; SR group, 82.4%; p=0.631). The cumulative 5-year incidence of esophageal cancer recurrence was 10.5% in the ER group (vs 0% in the SR group). The overall mortality rate was 12.9% (12.0% in the ER group and 15.9% in the SR group; p=0.399). The most common cause of mortality was second primary cancers in the ER group (75%) and organ dysfunction or postoperative complications in the SR group (70%). According to multivariate analysis, only CCI was significantly associated with OS (p<0.001). The 5-year OS rate in patients with a CCI >2 and in those with a CCI ≤2 was 60.2% and 88.2%, respectively (p<0.001). The treatment method (ER vs SR) was not a significant affecting factor (p=0.238).

Conclusions

The long-term prognosis of patients with T1aESCC was significantly associated with underlying comorbidities.

Patterns of Lymph Node Metastasis in Patients With T1/T2 Gastroduodenal Neuroendocrine Neoplasms: Implications for Endoscopic Treatment

Guidelines have differed in their opinion regarding the indications for endoscopic resection of gastric-neuroendocrine neoplasms (g-NENs) and duodenal-NENs (d-NENs). We examined the association between size and lymph node metastasis (LNM) to identify candidates most suitable for endoscopic resection. We identified 706 patients with T1/T2 g-NENs and 621 patients with T1/T2 d-NENs from the SEER database. The prevalence of LNM and risk factors associated with LNM were analyzed. LNM was present in 8.1% of patients with gastroduodenal neuroendocrine tumors (NETs) and 31.6% of patients with neuroendocrine carcinomas (NECs). Multivariate logistic regression indicated that tumor size >10mm, greater invasion depth, and poor differentiation were independently associated with LNM. In addition, the percentage of g-NETs invading submucosa with LNM increased with tumor size (≤10 mm,3.9%;11-20 mm,8.6%;>20 mm,16.1%). However, in contrast to the low LNM risk in patients with small g-NETs (≤10 mm), we found that LNM rate exceeded 5% even for patients with small submucosal-infiltrating d-NETs. Among patients with nodal-negative g-NETs, the cause specific survival (CSS) was similar for those who received surgical resection and endoscopic resection. Among patients with d-NETs, the CSS was better for those who received endoscopic resection. In conclusion, patients with d-NETs had a higher probability of LNM than those with g-NETs. Endoscopic resection can be utilized for curative treatment of submucosa-infiltrating g-NETs and intramucosal d-NETs when the size is 10 mm or less. These results reinforce the need to search for LNM in lesions that are larger than 10 mm.

Biological Guided Carbon-Ion Microporous Radiation to Tumor Hypoxia Area Triggers Robust Abscopal Effects as Open Field Radiation

Recently, a growing number of studies focus on partial tumor irradiation to induce the stronger non-target effects. However, the value of partial volume carbon ion radiotherapy (CIRT) targeting hypoxic region of a tumor under imaging guidance as well as its effect of inducing radiation induced abscopal effects (RIAEs) have not been well investigated. Herein, we developed a technique of carbon ion microporous radiation (CI-MPR), guided by ¹⁸F-FMISO PET/computerized tomography (CT), for partial volume radiation targeting the hypoxia area of a tumor and investigated its capability of inducing abscopal effects. Tumor-bearing mice were inoculated subcutaneously with breast cancer 4T1 cells into the flanks of both hind legs of mouse. Mice were assigned to three groups: group I: control group with no treatment; group II: carbon ion open field radiation (CI-OFR group) targeting the entire tumor; group III: partial volume carbon ion microporous radiation (CI-MPR group) targeting the hypoxia region. The tumors on the left hind legs of mice were irradiated with single fraction of 20 Gy of CIRT. Mice treated with CI-MPR or CI-OFR showed that significant growth delay on both the irradiated and unirradiated of tumor as compared to the control groups. Tumor regression of left tumor irradiated with CI-OFR was more prominent as compared to the tumor treated with CI-MPR, while the regression of the unirradiated tumor in both CI-MPR and CI-OFR group was similar. Biological-guided CIRT using the newly developed microporous technique targeting tumor hypoxia region could induce robust abscopal effects similar to CIRT covering the entire tumor.

Endoscopic Eradication Therapy for Barrett's Neoplasia: Where Do We Stand a Decade Later?

PURPOSE OF REVIEW

Barrett's esophagus (BE) is the only known precursor to esophageal adenocarcinoma (EAC), a cancer associated with increasing incidence and poor survival. Early identification and effective treatment of BE-related neoplasia prior to the development of invasive adenocarcinoma are essential to limiting the morbidity and mortality associated with this cancer. In this review, we summarized the recent evidence guiding endoscopic eradication therapies (EET) for neoplastic BE.

RECENT FINDINGS

New sampling technologies and the application of artificial intelligence (AI) systems have potential to revolutionize early neoplasia detection in BE. EET for BE are safe and effective in achieving complete eradication of intestinal metaplasia (CE-IM) and reducing the progression to EAC, a practice endorsed by all GI society guidelines. EET should be considered in patients with high-grade dysplasia (HGD), intramucosal carcinoma (IMC), and select cases with low-grade dysplasia (LGD). The increasing use of endoscopic submucosal dissection (ESD) in the West may allow EET of select cases with submucosal EAC. Post-EET surveillance strategies will continue to evolve as knowledge of specific risk factors and long-term neoplasia recurrence rates improve. In the last decade, major advancements in EET for neoplastic BE have been achieved. These now represent the standard of care in the management of BE-related dysplasia and intramucosal cancer.

Early vs. Delayed Feeding after Endoscopic Submucosal Dissection for Gastric Cancer: A Systematic Review and Meta-Analysis

Background: Endoscopic submucosal dissection (ESD) for gastric cancer is increasingly performed worldwide due to its efficacy and safety. This study aimed to assess the evidence of the impact of early vs. delayed feeding after ESD on quality of care, which remains to be fully determined. Methods: Electronic databases (PubMed, the Cochrane Central Register of Controlled Trials, EMBASE) and the trial registries (the World Health Organization International Clinical Trials Platform Search Portal and ClinicalTrials.gov) were searched for studies performed prior to September 2020. Study selection, data abstraction, and quality assessment were independently performed using the Grading of Recommendations Assessment, Development, and Evaluation approach. Self-rated satisfaction and hospital stay were chiefly analyzed. Results: Two randomized controlled trials (239 patients) were included. The early and delayed post-ESD feeding groups had similar rates of post-ESD bleeding (risk ratio 1.90, 95% CI 0.42 to 8.63; I² = 0%). Early post-ESD feeding resulted in increased patients’ satisfaction in comparison to delayed post-ESD feeding (standard mean difference (MD) 0.54, 95% CI 0.27 to 0.81; I² = 0%) and reduced the length of hospital stay (MD −0.83, 95% CI −1.01 to −0.65; I² = 0%). Conclusion: Early post-ESD feeding was associated with increased patients’ satisfaction and reduced hospital stay in comparison to delayed feeding, while the rate of complications did not differ to a statistically significant extent. As we must acknowledge the limited number of reviewed studies, various trials regarding the quality of care are further needed to determine the benefits of early feeding after ESD.

Results of laparoscopic intragastric surgery

BACKGROUND

Technological and operative advancements have allowed laparoscopic intragastric surgery (LIGS) to be applied in the treatment of superficial gastric or submucosal lesions. The aim of this study was to evaluate short- and long-term outcomes following LIGS.

METHODS

From 2000 to 2013, 25 LIGSs were performed for superficial gastric lesions. Clinical records were reviewed retrospectively for peri-operative course and long-term outcomes with particular attention to the oncological follow-up for patients with malignant lesions.

RESULTS

Nineteen (76%) lesions were located close to the EGJ, three (12%) in the lesser curvature, two (8%) in the posterior wall and one (4%) in the prepyloric-antral region. A multiport technique was used in 15 (60%) patients and a single-access approach in 10 (40%) patients. The median operative time was 140 (50-210) minutes. No conversion to open or conventional laparoscopic surgery was needed. Mortality was nil, and severe morbidity occurred in one (4%) patient. The median length of stay was 6 (3-10) days. Indications of LIGS were adenocarcinoma in 11 (44%) patients, gastrointestinal stromal tumors (GISTs) in 6 (24%) patients and benign lesions in eight (32%) patients. En bloc resection was obtained in 24 (96%) patients with R0 margins in 23 (92%) patients. After a median follow-up of 76 (26-171) months, recurrence was detected in 4 (36%) patients with advanced malignant adenocarcinoma.

CONCLUSION

LIGS provides an interesting alternative to major gastric and EGJ resection when endoscopic resection is not suitable for highly selected patients with superficial gastric lesions.

Successful Endoscopic Resection of Residual Colonic Mucosa-Associated Lymphoid Tissue Lymphoma after Polypectomy

Mucosa-associated lymphoid tissue (MALT) lymphomas are typically found in the stomach, while colonic MALT lymphoma is rarely found. Considering its rarity, definitive treatment of colonic MALT lymphoma has not been established. Different from that in the stomach, Helicobacter pylori infection might play a minor role while determining the treatment of colonic MALT lymphoma. If colonic MALT lymphoma is localized, treatment options are surgical resection, radiation, endoscopic resection, or combination therapy. Here, we report a case of residual colonic MALT lymphoma after endoscopic mucosal resection, which was a 1.5-cm-sized tumor confined to the superficial wall of the rectum. The lesion was successfully treated using the endoscopic submucosal dissection technique. The patient remained disease-free for 4 years. This case provides rationale for endoscopic submucosal dissection treatment as a salvage therapy for residual tumors in properly selected patients with colonic MALT lymphoma.

Comparable Cancer-Specific Mortality of Patients With Early Gastric Cancer Treated With Endoscopic Therapy vs Surgical Resection

BACKGROUND & AIMS

Endoscopic therapy is used commonly for superficial gastric cancer with very low risk of metastasis to the lymph nodes. However, limited population-based studies from the West have evaluated long-term outcomes of patients who received endoscopic therapy vs surgery.

METHODS

We used the Surveillance Epidemiology and End Results database to identify and compare features and outcomes of patients who underwent endoscopic therapy (n = 786) or surgery (n = 2577) for Tis or T1aN0M0 superficial gastric cancer, diagnosed from 1998 to 2014. Multivariate logistic regression was performed to identify factors associated with endoscopic therapy. Overall survival and gastric cancer-specific survival times were compared after we controlled for covariates.

RESULTS

Use of endoscopic therapy increased from 15.1% of cases in 1998 to 2000 to 39.0% of cases in 2013 to 2014. Endoscopic therapy was used more frequently in patients who were older, female, or Caucasian, or with lesions that were located in the proximal stomach or were limited in depth (Tis vs T1a) and size, compared with surgery. The median follow-up time was 59 months (interquartile range, 31-102 mo). Percentages of 5-year overall and cancer-specific survival were 57% and 99% in the endoscopic therapy group and 76% and 95% in the surgery group. After we adjusted for clinical factors using a multivariate Cox proportional hazards model, we found no significant difference in gastric cancer-specific mortality between patients who received endoscopic therapy vs surgery (hazard ratio, 1.42; 95% CI, 0.91-2.23; P = .12).

CONCLUSIONS

In an analysis of a large population database, we found an increased trend in endoscopic therapy for superficial gastric cancer compared with surgery from 1998 through 2014. Patients who received endoscopic therapy vs surgery had comparable long-term cancer-specific mortality.

Viscosity and degradation controlled injectable hydrogel for esophageal endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is a common procedure to treat early and precancerous gastrointestinal lesions. Via submucosal injection, a liquid cushion is created to lift and separate the lesion and malignant part from the muscular layer where the formed indispensable space is convenient for endoscopic incision. Saline is a most common submucosal injection liquid, but the formed liquid pad lasts only a short time, and thus repeated injections increase the potential risk of adverse events. Hydrogels with high osmotic pressure and high viscosity are used as an alternate; however, with some drawbacks such as tissue damage, excessive injection resistance, and high cost. Here, we reported a nature derived hydrogel of gelatin-oxidized alginate (G-OALG). Based on the rheological analysis and compare to commercial endoscopic mucosal resection (EMR) solution (0.25% hyaluronic acid, HA), a designed G-OALG hydrogel of desired concentration and composition showed higher performances in controllable gelation and injectability, higher viscosity and more stable structures. The G-OALG gel also showed lower propulsion resistance than 0.25% HA in the injection force assessment under standard endoscopic instruments, which eased the surgical operation. In addition, the G-OALG hydrogel showed good in vivo degradability biocompatibility. By comparing the results acquired via ESD to normal saline, the G-OALG shows great histocompatibility and excellent endoscopic injectability, and enables create a longer-lasting submucosal cushion. All the features have been confirmed in the living both pig and rat models. The G-OALG could be a promising submucosal injection agent for esophageal ESD.

•

Injectable gel with controlled viscosity.

•

Injectable gel with controlled degradation.

•

Making esophageal submucosal liquid cushion.

•

Potential treatment for early esophageal cancer.

•

Big animal in-situ imaging.

Life on a knife edge: the optimal approach to the management of perforations during endoscopic submucosal dissection (ESD)

INTRODUCTION

Endoscopic submucosal dissection (ESD) is a well-established procedure that can provide curative resection of malignant and premalignant lesions endoscopically, thereby offering patients an effective non-operative option. Though ESD is safe and highly effective when performed in appropriately selected patients by an experienced ESD expert, it carries risks including intraprocedural and delayed perforation.

AREAS COVERED

This review provides a practical approach to the initial management of perforation to minimize subsequent complications. The importance of prompt recognition of perforation and early intervention cannot be overstated. This review summarizes indications for closure, anatomic considerations impacting closure, and closure techniques. This article also highlights the do's and don'ts of various closure devices, focusing particularly on advanced closure methods, the-over-the-scope clips (OTSCs) and endoscopic suturing.

EXPERT OPINION

As ESD offers surgery-sparing alternatives to patients, advanced closure techniques allow endoscopists to effectively and promptly manage associated complications, improving the possibility of the widespread implementation of ESD in the US. With continued improvements in OTSCs and endoscopic suturing, ESD will become a stalwart of endoscopic management of malignant and premalignant gastrointestinal lesions.