Stricture after endoscopic submucosal dissection for early gastric cancers and adenomas

Effects on anorectal function of endoscopic submucosal dissection for rectal tumors involving the dentate line

OBJECTIVE

Endoscopic submucosal dissection (ESD) is a specific procedure that uses an electrosurgical knife for en-bloc resectioning large tumors. However, no study has examined the effect of ESD on the defecation function of patients with rectal tumors. We aimed to investigate the potential effects caused by ESD by analyzing changes in the morphology and movement of the anorectum pre- and post-ESD.

METHODS

This prospective observational study included 11 patients with anorectal tumors who underwent ESD between April 2020 and February 2022. Pre-ESD assessments included anorectal manometry and defecography. Post-ESD assessments were conducted 2 months later, including anorectal manometry, defecography, and proctoscopy for ulcer and stenosis evaluation.

RESULTS

The median patient age was 73 years, including seven males and four females. Eight patients (73%) had a tumor in the lower rectum, and the extent of resection was less than 50% of the rectal lumen. Resection reached the dentate line in six cases (55%). In the patients with post-ESD mucosal defects involving the dentate line, the median of functional anal canal length significantly decreased from (3.4 cm pre-ESD to 2.8 cm post-ESD, p = 0.04). Defecography revealed one case with incomplete evacuation (<50%) and incontinence post-ESD. Interestingly, patients with pre-existing rectoceles noted resolution of lesions post-ESD. None of the patients reported daily constipation or fecal incontinence.

CONCLUSIONS

While rectal ESD is unlikely to cause significant real-world defecation difficulties, alterations in rectal and anal canal morphology and function may occur if the dentate line is involved in the resection range.

Characteristics and Risk Factors of Delayed Perforation in Endoscopic Submucosal Dissection for Early Gastric Cancer

(1) Background: Delayed perforation after gastric endoscopic submucosal dissection (ESD) for early gastric cancer is a relatively uncommon and serious complication that sometimes requires emergency surgery. This study aimed to determine the clinicopathological features, risk factors, and appropriate management strategies for delayed perforation. (2) Methods: This study included 735 patients with 791 lesions who underwent ESD for early gastric cancer at a single institution between July 2009 and June 2019. We retrospectively compared the clinical features of patients with and without delayed perforations. (3) Results: The incidence of delayed perforations was 0.91%. The identified risk factors included a postoperative stomach condition and histopathological ulceration. A comparison between delayed and intraoperative perforations revealed a postoperative stomach condition as a characteristic risk factor for delayed perforation. Patients with delayed perforation who avoided emergency surgery tended to exhibit an earlier onset of symptoms such as abdominal pain and fever. No peritoneal seeding following delayed perforation was observed for any patient. (4) Conclusions: A postoperative stomach condition and histopathological ulceration were risk factors for delayed perforation. Delayed perforation is a significant complication that requires careful monitoring after gastric ESD for early gastric cancer, particularly in patients with postoperative gastric conditions.

The efficacy of newly proposed gastric open peroral endoscopic myotomy (GO-POEM) in preventing post-endoscopic submucosal dissection stenosis: A comparison with non-GO-POEM group

Extensive endoscopic submucosal dissection (ESD) for gastric adenoma or early cancer can lead to post-ESD stenosis. This may cause a decrease in quality of life and an increase in medical issues. Therefore, this study examined the safety and effectiveness of gastric open peroral endoscopic myotomy (GO-POEM) in preventing stenosis following ESD. A retrospective investigation was carried out on 31 patients who underwent gastric ESD for > 75% of the lumen in the antrum or pylorus at the Presbyterian Medical Center in Korea between December 2004 and October 2022. The patients were divided into GO-POEM (n = 11) and non-GO-POEM groups (n = 20). The average age of the 31 patients was 73.23 years, and 18 were male. There were no differences in age, sex, location, gross findings, or procedure time between the 2 groups. In the GO-POEM group, only 1 patient (9 %) developed stenosis, compared to 11 patients (55 %) in the control group (P = .02). Multivariate analysis showed that the GO-POEM group had a significantly lower risk of post-ESD stenosis (P < .05). Stenosis symptoms resolved with a single endoscopic balloon dilatation (EBD) in 1 patient in the GO-POEM group. In contrast, 5 of 11 patients with stenosis in the non-GO-POEM group required a median of 2 EBD sessions (range, 1-8). GO-POEM may be an effective and reliable method for preventing stenosis post extensive gastric ESD. Further investigations are necessary to establish its efficacy and safety.

Endoscopic submucosal dissection techniques and technology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review

ESGE suggests conventional endoscopic submucosal dissection (ESD; marking and mucosal incision followed by circumferential incision and stepwise submucosal dissection) for most esophageal and gastric lesions. ESGE suggests tunneling ESD for esophageal lesions involving more than two-thirds of the esophageal circumference. ESGE recommends the pocket-creation method for colorectal ESD, at least if traction devices are not used. The use of dedicated ESD knives with size adequate to the location/thickness of the gastrointestinal wall is recommended. It is suggested that isotonic saline or viscous solutions can be used for submucosal injection. ESGE recommends traction methods in esophageal and colorectal ESD and in selected gastric lesions. After gastric ESD, coagulation of visible vessels is recommended, and post-procedural high dose proton pump inhibitor (PPI) (or vonoprazan). ESGE recommends against routine closure of the ESD defect, except in duodenal ESD. ESGE recommends corticosteroids after resection of  > 50 % of the esophageal circumference. The use of carbon dioxide when performing ESD is recommended. ESGE recommends against the performance of second-look endoscopy after ESD. ESGE recommends endoscopy/colonoscopy in the case of significant bleeding (hemodynamic instability, drop in hemoglobin > 2 g/dL, severe ongoing bleeding) to perform endoscopic hemostasis with thermal methods or clipping; hemostatic powders represent rescue therapies. ESGE recommends closure of immediate perforations with clips (through-the-scope or cap-mounted, depending on the size and shape of the perforation), as soon as possible but ideally after securing a good plane for further dissection.

Closure of large mucosal defects for prevention of strictures after duodenal endoscopic submucosal dissection (with video)

BACKGROUND AND AIMS

Although lesions occupying a large circumference are associated with the risk of post-endoscopic submucosal dissection (ESD) strictures, the corresponding data for duodenal lesions are unknown. We aimed to analyze the incidence of post-ESD strictures after wide-field duodenal ESD.

METHODS

In this retrospective study of duodenal lesions treated with ESD between July 2010 and August 2021, we included lesions that resulted in mucosal defects occupying more than half of the circumference and excluded lesions located in bulbs and involving Vater's papilla. We analyzed the incidence rates of stricture and luminal narrowing, in addition to bleeding and perforation as the outcomes in this study. Stricture was defined as the inability of the endoscope to pass through the lumen. A single endoscopist reviewed all endoscopic images and judged the degree of luminal narrowing.

RESULTS

Eighty lesions were included, of which 2 involved mucosal defects occupying more than 90% of the circumference. The wound was closed, at least partially, in 90% in all lesions and in 86% of lesions with a mucosal defect occupying more than 75% of the circumference. None of the lesions caused delayed perforation and stricture, whereas 2 lesions caused delayed bleeding. Only 6 lesions caused luminal narrowing. When examined by the degree of closure, the rate of luminal narrowing increased with complete closure, incomplete closure, and nonclosure (4.9%, 9.1%, and 25.0%, respectively).

CONCLUSIONS

Suturing may prevent post-ESD bleeding and perforation as well as stricture formation in cases of duodenal tumors, with mucosal defects occupying a large circumference.

Demarcation Line Determination for Diagnosis of Gastric Cancer Disease Range Using Unsupervised Machine Learning in Magnifying Narrow-Band Imaging

Background and Aims: It is important to determine an accurate demarcation line (DL) between the cancerous lesions and background mucosa in magnifying narrow-band imaging (M-NBI)-based diagnosis. However, it is difficult for novice endoscopists. We aimed to automatically determine the accurate DL using a machine learning method. Methods: We used an unsupervised machine learning approach to determine the DLs. Our method consists of the following four steps: (1) an M-NBI image is segmented into superpixels using simple linear iterative clustering; (2) the image features are extracted for each superpixel; (3) the superpixels are grouped into several clusters using the k-means method; and (4) the boundaries of the clusters are extracted as DL candidates. The 23 M-NBI images of 11 cases were used for performance evaluation. The evaluation investigated the similarity of the DLs identified by endoscopists and our method, and the Euclidean distance between the two DLs was calculated. For the single case of 11 cases, the histopathological examination was also conducted to evaluate the proposed system. Results: The average Euclidean distances for the 11 cases were 10.65, 11.97, 7.82, 8.46, 8.59, 9.72, 12.20, 9.06, 22.86, 8.45, and 25.36. The results indicated that the proposed method could identify similar DLs to those identified by experienced doctors. Additionally, it was confirmed that the proposed system could generate pathologically valid DLs by increasing the number of clusters. Conclusions: Our proposed system can support the training of inexperienced doctors as well as enrich the knowledge of experienced doctors in endoscopy.

Prolonged ischemia of the ileum and colon after surgical mucosectomy explains contraction and failure of "mucus free" bladder augmentation

INTRODUCTION

Mucus production by the intestinal segment used in bladder augmentation results in long term concerns especially stones and UTI. Bladder augmentation with demucosalized intestinal flap is a potential promising approach for mucus-free bladder augmentation, however the contraction of the flap remains a major concern. Mucosectomy has been shown to result in abrupt and immediate cessation of microcirculation in the ileum. However, assessment of microcirculation shortly after mucosectomy may miss a gradual recovery of micro-circulation over a longer period of time. Previous studies have not assessed the colon response to mucosectomy.

OBJECTIVE

Our aim was to assess the effect of mucosectomy on the microcirculation of the colon and ileum beyond the known warm ischemia time.

STUDY DESIGN

Ileum and colon segments were detubularised and mucosectomy was performed in (n = 8) anesthetised minipigs. Group A: sero-musculo-submucosal flaps were created with removal of the mucosa and preserving the submucosal layer Group B: sero-muscular flaps were created with the removal of submucosal-mucosal layer. The Microvascular Flow Index (MFI), the velocity of the circulating red blood cells (RBCV) was measured using Intravital Dark Field (IDF) side stream videomicroscopy (Cytoscan Braedius, The Netherlands) after mucosectomy, for up to 180 min.

RESULTS

Both the MFI and RBCV showed an abrupt reduction of microcirculation, on both surfaces of the remaining intestinal flap, in the ileum as well as in the colon. Slightly better values were seen in Group A of the colon, but even these values remain far below the preoperative (control) results. Some, tendency of recovery of the microcirculation was noted after 60-90 min, but this remained significantly lower than the preoperative control values at 180 min.

CONCLUSION

Both the ileal and the colonic flap remains in severe ischemia after mucosectomy beyond the warm ischemia time.

DISCUSSION

This study shows that surgical mucosectomy compromises vascular integrity of the intestinal flaps used for bladder augmentation. Partial recovery which occurs within the warm ischemia time is not significant enough to avoid fibrosis therefore flap shrinkage may be inevitable with this technique.

LIMITATION

The gastrointestinal structure of the porcine model is not the same exactly as the human gastrointestinal system. However, although not an exact match it is the closest, readily available animal model to the human gastrointestinal system.

The Safety and Clinical Validity of Endoscopic Submucosal Dissection for Early Gastric Cancer in Patients Aged More Than 85 Years

Endoscopic submucosal dissection (ESD) is a safe and minimally invasive method for the treatment of early gastric cancer (EGC). However, whether ESD for EGC is also safe and feasible in patients aged ≥85 years is unclear. The patients enrolled in this study were divided into three groups: age ≥85 years (44 patients, 49 lesions), age 65−84 years (624 patients, 687 lesions), and age ≤64 years (162 patients, 174 lesions). We evaluated the incidence of adverse events (AEs) and overall survival (OS) and disease-specific survival (DSS). We analyzed the factors that had a significant impact on the prognosis of patients aged ≥85 years. No significant differences were found in the incidence of AEs among the three groups (p = 0.612). The OS was significantly lower in patients aged ≥85 years (p < 0.001). Conversely, DSS was not significantly worse in patients aged ≥85 years (p = 0.100). The poor Geriatric Nutritional Risk Index correlated with poor prognosis in patients aged ≥85 years (p < 0.001). ESD is a safe and valid treatment for EGC in patients aged ≥85 years. However, the indications should be carefully decided because it is difficult to estimate the survival contribution of ESD for EGC in patients aged ≥85 years, especially in those with poor nutritional status.

Safety and efficacy of prophylactic gastric open peroral endoscopic myotomy for prevention of post-ESD stenosis: A case series (with video)

OBJECTIVE

Endoscopic resection of over 3/4 of the lumen of the antrum or pylorus is a known risk factor for post-endoscopic submucosal dissection (ESD) stenosis. Local or systemic steroids may reduce the risk of stenosis, but their overall role in stenosis prevention remains controversial. We aimed to evaluate the efficacy and safety of prophylactic gastric open peroral endoscopic myotomy (GO-POEM) in preventing post-ESD stenosis.

METHODS

Ten patients who underwent GO-POEM during or immediately after ESD in the Presbyterian Medical Center between June 2017 and November 2020 were included. All patients underwent excision of over 3/4 of the lumen of the antrum or pylorus. GO-POEM was performed without submucosal tunneling.

RESULTS

Well-differentiated tubular adenocarcinoma, tubulovillous adenoma with high-grade dysplasia, and tubular adenoma with low-grade dysplasia were diagnosed in three, one, and six patients, respectively. GO-POEM was performed successfully in all the 10 patients. Stenosis could not be evaluated in one patient, whereas one of the remaining nine patients developed post-ESD stenosis. GO-POEM decreased the risk of post-ESD stenosis in the other eight patients. Two patients presented with intraprocedural bleeding, both of whom were managed endoscopically successfully.

CONCLUSIONS

Prophylactic GO-POEM may be a novel, effective and safe treatment modality for preventing post-ESD stenosis in the stomach. Well-designed, multicenter studies with large sample sizes are needed to confirm our results.

Timing of pyloric stenosis and effectiveness of endoscopic balloon dilation after pyloric endoscopic submucosal dissection

BACKGROUND AND AIM

There have been studies on risk factors for stenosis after pyloric endoscopic submucosal dissection (ESD). However, the most appropriate strategies for the management of cases with these risk factors have not been established. This study aimed to investigate post-ESD management by evaluating the timing of stenosis and the effectiveness of endoscopic balloon dilation (EBD) after pyloric ESD.

METHODS

We retrospectively reviewed cases of pyloric ESD. We first reassessed risk factors for stenosis in multivariate analysis and receiver operating characteristic curve and defined patients with the identified risk factors as the risk group. The primary outcome was the timing of stenosis in the risk group assessed by the Kaplan-Meier method.

RESULTS

We reviewed 159 cases with pyloric ESD and observed pyloric stenosis in 25 cases. Cases with circumferential mucosal defect ≥ 76% were identified as the risk group. The stenosis-free probability in the risk group was 97% (95% confidence interval [CI]: 79-100%), 94% (95% CI: 76-98%), and 85% (95% CI: 66-93%) on days 7, 14, and 21, respectively. It decreased every week thereafter and did not significantly change after day 56. Twenty-three stenosis cases, except for conservative improvement, including six whole circumferential pyloric ESD cases, were improved by EBD without complications.

CONCLUSIONS

Post-ESD stenosis often developed from the third to the eighth week. In all pyloric ESD cases, including whole circumferential pyloric ESD cases, pyloric stenosis was improved following EBD without complications.

Simultaneous laparoscopic hiatal hernia repair and pyloroplasty for a type 3 hiatal hernia with post-ESD pyloric stenosis for early gastric cancer

We present a case of early gastric cancer in the pylorus with a type 3 hiatal hernia, which was treated by endoscopic submucosal dissection (ESD). A 70-year-old man was referred to our hospital with a hiatal hernia. Endoscopy revealed early gastric cancer, and we performed an ESD adaptation at the pylorus. The ESD was successful, but post-ESD pyloric stenosis occurred. Symptoms of hiatal hernia worsened because of the pyloric stenosis. Laparoscopic hiatal hernia repair with Toupet fundoplication and Heineke-Mikulicz pyloroplasty was simultaneously performed. The postoperative course was good, and follow-up after discharge was uneventful. To our knowledge, there have been no reports in which laparoscopic hiatal hernia repair, fundoplication, and pyloroplasty were simultaneously performed for a substantial hiatal hernia with post-ESD pyloric stenosis.

Intraperitoneal Abscess as a Postoperative Complication of Gastric Endoscopic Submucosal Dissection

We herein report a case of intraperitoneal abscess as a postoperative complication of gastric endoscopic submucosal dissection (ESD). A 70-year-old man who underwent ESD for early gastric cancer sought consultation for abdominal pain on postoperative day 28. Abdominal computed tomography revealed intraperitoneal abscess rupture. He underwent image-guided laparoscopic irrigation. His postoperative course was favorable, and he was discharged after 27 days. Intraoperatively, a white plaque adhering to the gastric wall was surrounded by a large pus volume and suspected to be ESD-associated. We present this case with a literature review of the association between intraperitoneal abscess and ESD.

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.

Experiment on endoscopic balloon dilation for esophageal stenosis after endoscopic submucosal dissection in pigs

BACKGROUND AND AIM

Endoscopic balloon dilation (EBD) is effective for esophageal stenosis caused by ESD. However, an efficient EBD method has not been established. We, therefore, conducted EBD experiments on porcine esophageal stenosis models.

METHODS

Study 1: in dilation models (day 22 after ESD), the thickness of the outer muscle layer (as an index of the extension effect) and the area of muscle fiber bundle necrosis in the inner muscle layer (as an index of thermal damage) were evaluated. Study 2: in restenosis models (day 43 after ESD), the thickness of the fibrous plexus (as an index of restenosis) was evaluated. In total, 12 porcine models were created.

RESULTS

Study 1: the thickness of the outer muscle layer was 1243 ± 322 μm in surrounding locations and it was 803 ± 145 μm beneath the laceration (p = 0.005). In cases of muscular layer injury, the area of necrosis was 15,500 ± 10400 μm² in surrounding locations and it was 40,200 ± 12900 μm² at the laceration site (p < 0.001). Study 2: the thickness of the fibrous plexus was 1359 ± 196 μm in surrounding locations and it was 1322 ± 136 μm² in the laceration scar site (p = 0.74).

CONCLUSION

Since thermal damage persists until the completion of stenosis, EBD in the initial stage should be carefully performed. An extension effect was observed only at the laceration site and it later returned to a status similar to that of surrounding locations. Additional intervention would be required for preventing restenosis.

A deep learning-based system for identifying differentiation status and delineating the margins of early gastric cancer in magnifying narrow-band imaging endoscopy

BACKGROUND : Accurate identification of the differentiation status and margins for early gastric cancer (EGC) is critical for determining the surgical strategy and achieving curative resection in EGC patients. The aim of this study was to develop a real-time system to accurately identify differentiation status and delineate the margins of EGC on magnifying narrow-band imaging (ME-NBI) endoscopy. METHODS : 2217 images from 145 EGC patients and 1870 images from 139 EGC patients were retrospectively collected to train and test the first convolutional neural network (CNN1) to identify EGC differentiation status. The performance of CNN1 was then compared with that of experts using 882 images from 58 EGC patients. Finally, 928 images from 132 EGC patients and 742 images from 87 EGC patients were used to train and test CNN2 to delineate the EGC margins. RESULTS : The system correctly predicted the differentiation status of EGCs with an accuracy of 83.3 % (95 % confidence interval [CI] 81.5 % - 84.9 %) in the testing dataset. In the man - machine contest, CNN1 performed significantly better than the five experts (86.2 %, 95 %CI 75.1 % - 92.8 % vs. 69.7 %, 95 %CI 64.1 % - 74.7 %). For delineating EGC margins, the system achieved an accuracy of 82.7 % (95 %CI 78.6 % - 86.1 %) in differentiated EGC and 88.1 % (95 %CI 84.2 % - 91.1 %) in undifferentiated EGC under an overlap ratio of 0.80. In unprocessed EGC videos, the system achieved real-time diagnosis of EGC differentiation status and EGC margin delineation in ME-NBI endoscopy. CONCLUSION : We developed a deep learning-based system to accurately identify differentiation status and delineate the margins of EGC in ME-NBI endoscopy. This system achieved superior performance when compared with experts and was successfully tested in real EGC videos.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer (second edition)

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society, in collaboration with the Japanese Gastric Cancer Association, produced "Guidelines for Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection for Early Gastric Cancer" in 2014, as a set of basic guidelines in accordance with the principles of evidence-based medicine. At the time, a number of statements had to be established by consensus (the lowest evidence level), as evidence levels remained low for many specific areas in this field. However, in recent years, the number of well-designed clinical studies has been increasing. Based on new findings, we have issued the revised second edition of the above guidelines that cover the present state of knowledge. These guidelines are divided into the following seven categories: indications, preoperative diagnosis, techniques, evaluation of curability, complications, long-term postoperative surveillance, and histology.

Strategies for treating oesophageal diseases with stem cells

There is a wide range of oesophageal diseases, the most general of which are inflammation, injury and tumours, and treatment methods are constantly being developed and updated. With an increasingly comprehensive understanding of stem cells and their characteristics of multilineage differentiation, self-renewal and homing as well as the combination of stem cells with regenerative medicine, tissue engineering and gene therapy, stem cells are playing an important role in the treatment of a variety of diseases. Mesenchymal stem cells have many advantages and are most commonly applied; however, most of these applications have been in experimental studies, with few related clinical trials for comparison. Therefore, the methods, positive significance and limitations of stem cells in the treatment of oesophageal diseases remain incompletely understood. Thus, the purpose of this paper is to review the current literature and summarize the efficacy of stem cells in the treatment of oesophageal diseases, including oesophageal ulceration, acute radiation-induced oesophageal injury, corrosive oesophageal injury, oesophageal stricture formation after endoscopic submucosal dissection and oesophageal reconstruction, as well as gene therapy for oesophageal cancer.

Analysis of factors associated with local recurrence after endoscopic resection of gastric epithelial dysplasia: a retrospective study

Background

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are widely used techniques for the treatment of gastric epithelial dysplasia. Previous studies have compared the clinical outcome of endoscopic resection for early gastric cancer, but few studies have focused on gastric dysplasia alone. This study aimed to evaluate the long-term prognosis following endoscopic procedures for gastric epithelial dysplasia, investigate differences in local recurrence rates according to the treatment modality, and identify risk factors associated with local recurrence.

Methods

In this retrospective study, local recurrence rates and risk factors associated with local recurrence were compared between 599 patients who underwent EMR and 306 who underwent ESD for gastric epithelial dysplasia from January 2011 to December 2015.

Results

The en bloc resection rate (32.2% vs. 100%, p < 0.001) and complete resection rate (94.8% vs. 99.0%, p = 0.003) were significantly lower in the EMR group than in the ESD group. The local recurrence rate was significantly lower in the ESD group (1.3%) than in the EMR group (4.2%; p = 0.026). There was a significantly increased risk of local recurrence, regardless of lesion location or histologic grade, in patients with lesions > 2 cm (p = 0.002) or red in color (p = 0.03). The ESD group had a significantly lower local recurrence rate, with a higher complete resection rate, than that in the EMR group (p < 0.05). In the case of recurrence after endoscopic resection, most of the recurred lesions were removed through additional endoscopic procedures; there was no difference between the two groups (p = 0.153).

Conclusions

The complete resection rate was significantly higher, and the local recurrence rate was significantly lower, in patients with gastric epithelial dysplasia treated with ESD. Therefore, ESD should be considered the preferred treatment in patients with lesions > 2 cm or showing redness due to an increased risk of local recurrence and EMR may be possible for low-grade dysplasia that is less than 2 cm without surface changes such as redness, depression and nodularity.

Endoscopic submucosal dissection involving the anal canal presents a risk factor for postoperative stricture

BACKGROUND

Although postoperative strictures after endoscopic submucosal dissection (ESD) in the rectum are relatively rare, some rectal lesions require resection involving the anal canal, which is a narrow tract comprising squamous epithelium. To the best of our knowledge, no studies have investigated narrow anal canals when evaluating post-ESD strictures. This study aimed to evaluate the impact of resections involving the anal canal on postoperative stricture development.

METHODS

Between April 2005 and October 2017, 707 rectal lesions were treated with ESD. We retrospectively investigated 102 lesions that required ≥ 75% circumferential resection. Risk factors for post-ESD stricture and, among patients with strictures, obstructive symptoms, and number of dilation therapies required were investigated.

RESULTS

Post-ESD stricture occurred in 18 of 102 patients (17.6%). In the multivariate analysis, circumferential resection ≥ 90% and ESD involving the anal canal (ESD-IAC) were risk factors for postoperative strictures (P ≤ 0.0001 and 0.0115, respectively). Among the patients with strictures, obstructive symptoms were significantly related to anal strictures compared to rectal strictures (100% vs. 27.2%, P = 0.0041). Furthermore, the number of dilation therapies required was significantly greater among patients with anal strictures compared to those with rectal strictures (6.5 times vs. 2.7 times, P = 0.0263).

CONCLUSION

Not only circumferential resection ≥ 90% but also ESD-IAC was a significant risk factor for the stricture after rectal ESD. Furthermore, anal strictures were associated with a significantly higher frequency of obstructive symptoms and larger number of required dilation therapies than were rectal strictures.

A potential simple endoscopic antireflux method, "the Ripple Procedure" to reduce distensibility at the esophagogastric junction in a porcine model

BACKGROUND AND AIMS

Currently available endoscopic or minimally invasive antireflux modalities are not widely accepted due to high procedure cost or inconsistent results. Therefore, a simpler and less technically demanding method is required. We evaluated the feasibility and efficacy of new endoscopic antireflux method (the Ripple Procedure) using functional lumen imaging probe (FLIP).

METHODS

This 5-week survival study included 10 domestic pigs (control, n = 4; experimental [Ripple], n = 6). The procedure includes the following steps: (i) semicircular marking along the lesser curvature of the cardia; (ii) submucosal injection; and (iii) semicircular mucosal incision along the marking. Endoscopic and FLIP evaluations were performed preoperatively and on postoperative days (PODs) 14 and 35. Technical feasibility was evaluated, and FLIP parameters, including the distensibility index (DI) at the esophagogastric junction (EGJ) and histopathological findings, were compared between groups.

RESULTS

The median procedure time was 28 (23.5-33.8) min. There was no significant difference in dysphagia score and body weight between groups. On POD 35, the Ripple group showed significantly lower EGJ DI at 30 mL [2.0 (1.3-2.5) vs 4.9 (2.7-5.0), P = 0.037]. The EGJ DI was significantly reduced at 30 mL, compared with that at the baseline level [- 59.0% (- 68.8% to - 32.1%) vs 27.8% (- 26.3% to 83.1%), P = 0.033]. Histologic evaluation revealed submucosal granulation tissues near the mucosal incision site, with increased intervening fibrosis between lower esophageal sphincter fibers in the Ripple group.

CONCLUSION

The EGJ DI significantly decreased after the Ripple Procedure; hence, the procedure appears to be feasible and effective in this porcine model.

Management of adverse events related to endoscopic resection of upper gastrointestinal neoplasms: Review of the literature and recommendations from experts

Prevention therapy is recommended for lesions >1/2 of the esophageal circumference. Locoregional steroid injection is recommended for lesions >1/2-3/4 of the esophageal circumference and oral steroids are recommended for lesions >1/2 of the subtotal circumference. For lesions of the entire circumference, oral steroid combined with injection steroid is considered. Endoscopic balloon dilatation (EBD) is the first choice of treatment for stricture after esophageal endoscopic submucosal dissection (ESD). Radical incision and cutting or self-expandable metallic stent can be considered for refractory stricture after EBD. In case of intraoperative perforation during esophageal ESD, endoscopic clip closure should be initially attempted. Surgery is considered for treatment of delayed perforation. Current standard practice for prevention of delayed bleeding after gastric ESD includes prophylactic coagulation of vessels on post-ESD ulcers and giving proton pump inhibitors. Chronic kidney disease stage 4 or 5, multiple antithrombotic drug use, anticoagulant use, and heparin bridging therapy are high-risk factors for delayed bleeding after gastric ESD. Intraoperative perforation during gastric ESD is initially managed by endoscopic clip closure. If endoscopic clip closure is difficult, other methods such as over-the-scope clip (OTSC), polyglycolic acid (PGA) sheet shielding etc. are attempted. Delayed perforation usually requires surgical intervention, but endoscopic closure by OTSC or PGA sheet may be considered. Resection of three-quarters of the circumference is a risk factor for stenosis after gastric ESD. Giving prophylactic local steroid injection and/or oral steroid is reported, but effectiveness has not been fully verified as has been done for esophageal stricture. The main management method for gastric stenosis is EBD but it may cause perforation.

Management of Complications of Colorectal Submucosal Dissection

Endoscopic submucosal dissection (ESD) is a useful procedure for the treatment of superficial gastrointestinal neoplasm. Compared with endoscopic mucosal resection (EMR), ESD has several benefits, which include resectability of various difficult lesion, accurate histologic assessment of specimen, and lower recurrence rate. However, the risk of procedure- related complications is higher with ESD than with EMR. Moreover, because the colon has a thin wall and limited endoscopic maneuverability, ESD is considered a more challenging and risky procedure when performed in the colon than in the stomach. ESD-related complications are more likely to occur. The significant complications associated with ESD are bleeding, perforation, coagulation syndrome and stenosis, most of which can be treated and prevented by endoscopic intervention and preparation. Therefore, it is important to know how to occur and manage the ESD related complication.

Laparoscopic and endoscopic cooperative surgery for intra-mucosal gastric carcinoma adjacent to the ulcer scars

Background

Laparoscopic and endoscopic cooperative surgery (LECS) was performed for the local resection of gastrointestinal stromal tumors (GIST). LECS enables less resection of the lesion area and preserves function. Furthermore, LECS can be safely performed and independent of tumor location. However, LECS is not usually used for cases involving gastric carcinoma because it may seed tumor cells into the peritoneal cavity when the gastric wall is perforated. Here, we report seven cases of LECS for intra-mucosal gastric carcinoma, which were difficult to carry out by endoscopic submucosal dissection (ESD) because of ulcer scars.

Methods

We performed LECS (classical LECS and inverted LECS) in seven cases of intra-mucosal gastric carcinoma. All cases had ulcer scars beside the tumor. LECS was chosen because ESD was thought to be difficult because of the ulcer scars. We only selected cases in which the patients did not prefer gastrectomy and endoscopic examination was indicative of intra-mucosal gastric carcinoma.

Results

In all cases, LECS was performed without severe complications including postoperative stenosis. Histopathology findings proved that the tumors were intra-mucosal carcinoma and had been resected completely. Furthermore, there were ulcer scars (Ul IIIs-IVs) beside the tumor. Currently, dissemination and recurrence have not been apparent.

Conclusions

LECS for intra-mucosal gastric carcinoma is an efficient procedure, but strict observation is necessary because of the possibility of peritoneal dissemination. Results suggest that LECS is likely to be effective for cases involving intra-mucosal gastric carcinoma that are difficult to treat by ESD due to ulcer scars.

Oral administration of conditioned medium obtained from mesenchymal stem cell culture prevents subsequent stricture formation after esophageal submucosal dissection in pigs

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) for esophageal cancer often causes postoperative stricture when more than three fourths of the circumference of the esophagus is dissected. Mesenchymal stem cells are a valuable cell source in regenerative medicine, and conditioned medium (CM) obtained from mesenchymal stem cells reportedly inhibits inflammation. In this study we evaluated whether CM could prevent esophageal stricture after ESD.

METHODS

We resected a semi-circumference of pig esophagus by ESD. We prepared CM gel by mixing with 5% carboxymethyl cellulose and endoscopically applied it onto the wound bed immediately after ESD and on days 8 and 15 (weekly CM group) or administered it orally from days 1 to 4 (daily CM group). We also injected triamcinolone acetonide into the remaining submucosa immediately after ESD (steroid group). We killed the pigs on day 8 or day 22 to measure the stricture rate and to perform histologic analysis.

RESULTS

Stricture rate in weekly and daily CM groups and steroid groups were significantly lower than in the control group on day 22. Moreover, CM significantly attenuated the number of activated myofibroblasts and fiber thickness on day 22. CM also significantly decreased the infiltration of neutrophils and macrophages compared with the control group on day 8.

CONCLUSIONS

CM gel prevents esophageal stricture formation by suppressing myofibroblast activation and fibrosis after the infiltration of neutrophils and macrophages. Oral administration of CM gel is a promising treatment for the prevention of post-ESD stricture.

Management and risk factor of stenosis after endoscopic submucosal dissection for colorectal neoplasms

BACKGROUND AND AIM

Although endoscopic submucosal dissection (ESD) enables en bloc removal of large colorectal neoplasms, the incidence of stenosis after ESD and its risk factors have not been well described. This study aimed to determine the risk factors of stenosis and verify the surveillance and treatment of stenosis.

METHODS

This retrospective study included 822 patients, with a total of 912 consecutive colorectal lesions, who underwent ESD from September 2003 to May 2015. The main outcome measures were incidence of stenosis and its relationship with the clinicopathologic factors in surveillance.

RESULTS

Surveillance endoscopy was performed 6 months after ESD. Four of the 822 patients (0.49%) developed stenosis and required unanticipated endoscopy. The other 908 cases in 818 patients showed no symptoms or only slight abdominal discomfort (that was controlled with medication) and did not require any dilation or steroid therapies. Post-ESD stenosis was observed in 11.1% (2/18) of patients with circumferential resection between ≥90% and <100% and in 50% (2/4) of patients with circumferential resection of 100%. Among the 50 cases with a circumferential mucosal defect ≥75%, a circumferential mucosal defect ≥90% was a significant risk factor (P = .005). Four patients with stenosis were treated successfully by endoscopic dilation.

CONCLUSIONS

Circumferential mucosal defect of more than 90% is a significant risk factor for stenosis after colorectal ESD. Surveillance endoscopy 6 months after ESD is recommended to assess for development of stenosis. Defects smaller than 90% do not require close endoscopic follow-up or prophylactic measures for prevention of post-ESD stenosis. (UMIN clinical trial registration number: UMIN000015754.).

Antral or Pyloric Deformity Is a Risk Factor for the Development of Postendoscopic Submucosal Dissection Pyloric Strictures

BACKGROUND/AIMS

Surgeons must be aware of risk factors for strictures before performing endoscopic submucosal dissection (ESD), to enable early interventions to prevent severe strictures.

METHODS

This study was a single-center retrospective study. We reviewed the clinical data of patients who has undergone gastric ESD from January 2007 to December 2012.

RESULTS

Among the 3,819 patients who had undergone gastric ESD, 11 patients (7.2%) developed pyloric strictures and received successful endoscopic balloon dilation. Significant differences were noted between the patients without and with post-ESD strictures for pretreatment of antral or pyloric deformities (46.4% vs 81.8%), the proportion of extension to the lumen circumference (>3/4, 9.4% vs 54.5%), the longitudinal extent of mucosal defects (27.9±10.1 mm vs 51.5±10.8 mm), and post-ESD bleeding (2.9% vs 27.3%). Multivariate analysis revealed that pretreatment antral or pyloric deformities (odds ratio [OR], 30.53; 95% confidence interval [CI], 1.476 to 631.565; p=0.027), larger longitudinal extent of mucosal defects (OR, 1.20; 95% CI, 1.074 to 1.340; p=0.001), and circumferential extension of ≥3/4 (OR, 13.69; 95% CI, 1.583 to 118.387; p=0.017) were independent risk factors for post-ESD stricture.

CONCLUSIONS

Antral or pyloric deformities, sub-circumferential resection over more than 75% of the circumference and greater longitudinal extent of mucosal defects are independent risk factors for post-ESD stricture.

Risk factors and management for gastric stenosis after endoscopic submucosal dissection for gastric epithelial neoplasm

BACKGROUND

Only a few studies have reported treatment options for stenosis after endoscopic submucosal dissection (ESD) for gastric neoplasms. This study aimed to identify the risk factors for and evaluate the management of stenosis after ESD for gastric epithelial neoplasms in the cardia and antrum.

METHODS

We retrospectively reviewed 1218 patients (1447 gastric epithelial neoplasms) who underwent ESD at Tonan Hospital from June 2004 to November 2015. Post-ESD stenosis was defined when a standard endoscope could not be passed through the site.

RESULTS

Post-ESD stenosis occurred in 10 (21.3%) of the 47 cardia cases and 14 (3.2%) of the 432 antrum cases. A wide resection of more than three fourths of the circumferential extent was the sole significant risk factor related to post-ESD stenosis in both cardia and antrum. Prophylactic endoscopic balloon dilation (EBD) was performed in 3 of 10 patients with cardiac stenosis and 4 of 14 with antral stenosis. Post-EBD bleeding occurred in one cardia (10%) and one antrum (7.1%) case each and was endoscopically treated. Perforation during EBD occurred in two (14.3%) antrum cases, both of which required emergency open surgery. All complications were observed in patients with conventional EBD, and no complications were associated with prophylactic EBD.

CONCLUSIONS

A wide resection of more than three fourths of the circumferential extent was the significant risk factor for post-ESD stenosis in both cardia and antrum, and prophylactic EBD could be a promising procedure for the management of post-ESD stenosis.

Comparative study between endoscopic submucosal dissection and surgery in patients with early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) is accepted as a standard treatment in patients with early gastric cancer (EGC) who have a negligible risk of lymph node metastasis. The aim of this study was to compare the short-term and long-term outcomes between ESD and surgery in patients with EGC that fulfilled the expanded indication of ESD on their final pathologic report.

METHODS

We reviewed the clinical data of patients who underwent gastric ESD and surgery between January 2007 and December 2012. Patients with pathologically confirmed EGC that fulfilled the expanded indication of ESD on their final pathologic report were analyzed.

RESULTS

Among 2023 patients, 817 (40.4%) underwent ESD and 1206 (59.6%) underwent surgery. The proportion of cases meeting the absolute indication was significantly higher in the ESD group than in the surgery group (66.0 vs. 26.2%). Lesions on the middle third, >3 cm in size, flat or depressed, and of undifferentiated histology were significantly more common in the surgery group than in the ESD group. The ESD group showed lower acute complication rates [8.1% (66 of 817) vs. 18.1% (218 of 1206), P ≤ 0.001] and procedure-related mortality [0 vs. 0.3% (4 of 1206), P = 0.153] than the surgical group. The annual incidence of recurrent gastric cancer was 2.18% in the ESD group and 0.19% in the surgery group. The 5-year overall and disease-specific survival rates were not significantly different between the ESD group and the surgery group (overall survival: 96.4 vs. 97.2%, P = 0.423; disease-specific survival: 99.6 vs. 99.2%, P = 0.203).

CONCLUSIONS

Although EGC lesions had poorer features in the surgery group than in the ESD group, ESD was comparable to surgery for EGCs that fulfilled the expanded indication of ESD, with lower rates of acute complication and comparable overall survival.

Risk factors and management for pyloric stenosis occurred after endoscopic submucosal dissection adjacent to pylorus

Endoscopic submucosal dissection (ESD) has been widely accepted as a curative treatment for gastric neoplasm. Pyloric stenosis is a chronic complication that can be caused by ESD. The aim of this study is to clarify the risk factors and management for pyloric stenosis. From January 2004 to January 2014, a total of 126 patients who underwent ESD adjacent to pylorus were reviewed retrospectively. Pyloric mucosal defect was defined as when any resection margin of ESD was involved in the pyloric ring. Pyloric stenosis was defined as when a conventional endoscope could not be passed to the duodenum. Among the 126 patients, pyloric stenosis was identified in 9. In a univariate analysis, pyloric stenosis was more common in older patients (P < 0.05) and in lesions with resections over 75% of the pyloric ring circumference (P < 0.001). In a multivariate analysis, the factor that was associated with pyloric stenosis was the extent of the pyloric ring dissection (P < 0.001). Four of the 9 patients with pyloric stenosis had mild dyspepsia, and the others had gastric outlet obstruction symptoms. The 5 symptomatic patients underwent endoscopic balloon dilation (EBD), and the frequency of EBD was 1 to 8 times. The asymptomatic patients were treated conservatively. The incidence of pyloric stenosis was higher in lesions with resections over 75% of the pyloric ring circumference. Although EBD was an effective treatment for pyloric stenosis, conservative management was also helpful in patients who had mild symptoms.

Magnifying endoscopy with narrow-band imaging is more accurate for determination of horizontal extent of early gastric cancers than chromoendoscopy

BACKGROUND AND STUDY AIMS

Although magnifying endoscopy with narrow-band imaging (ME-NBI) is reported to be useful for delineating the horizontal extent of early gastric cancers (EGCs), there are few reports which have objectively demonstrated the superiority of ME-NBI over chromoendoscopy with indigo carmine for this purpose. We conducted an exploratory comparison of the diagnostic accuracy of both modalities for the delineation of EGCs using prospectively collected data, and clarified the clinicopathological features related to inaccurate evaluation of the horizontal extent of EGCs.

PATIENTS AND METHODS

EGCs were assigned to the oral narrow-band imaging (O-NBI) group or the oral chromoendoscopy (O-CE) group before endoscopic submucosal dissection (ESD). The oral border was observed according to assignment, and the anal border with the other modality. The horizontal extent of the tumor was evaluated by each modality and a marking dot was placed on the visible delineation line. After ESD, the marking dots were identified pathologically and defined as "accurate evaluation" if they were located within 1 mm of the pathological tumor border. We compared the rate of accurate evaluation of ME-NBI and chromoendoscopy, and analyzed the clinicopathological features related to inaccurate evaluation.

RESULTS

A total of 113 marking dots evaluated by ME-NBI and 116 evaluated by chromoendoscopy were analyzed. The rate of accurate evaluation by ME-NBI was significantly higher than that by chromoendoscopy (89.4 % vs 75.9 %, P = 0.0071). The EGCs with flat borders and large EGCs were significantly related to inaccurate evaluation using ME-NBI. There were no significant factors related to inaccurate evaluation with chromoendoscopy.

CONCLUSIONS

The accurate evaluation rate of the horizontal extent of EGCs by ME-NBI is significantly higher than that by chromoendoscopy.

STUDY REGISTRATION

UMIN000007641.

Endoscopic antralplasty for severe gastric stasis after wide endoscopic submucosal dissection in the antrum

A 75-year-old female underwent esophagogastroduodenoscopy, revealing a widely spreading tumor occupying the anterior wall, lesser curvature, and posterior wall of the antrum and lower body. Endoscopic submucosal dissection was performed and resulted in more than five-sixths circumferential antral mucosal resection. One month later, she complained of nausea, vomiting, and abdominal distention. Endoscopy showed residual food in the stomach and deformation of the antrum with traction toward the contracted scar in the lesser curvature. The pyloric ring could not be seen from the antrum although the endoscope was able to pass easily beyond the area of deformation and the pyloric ring was intact. Despite repeated endoscopic balloon dilations, the patient’s symptoms remained refractory. The problem was speculated to be not due to any potential stricture but to antrum deformation resulting from the traction force toward the healing ulcer. We hypothesized that an additional countertraction force opposite the previous ESD site might resolve the problem, and ESD of approximately 2.5 cm size was performed in the greater curvature of the antrum. Along with development of a scar, traction toward the greater curvature was added, and the pyloric ring could be observed on repeat esophagogastroduodenoscopy. The symptoms were also gradually ameliorated. Afterwards, the endoscopic findings have now been unchanged during 7 years of follow-up.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society (JGES), in collaboration with the Japanese Gastric Cancer Association (JGCA), has produced 'Guidelines for ESD and EMR for Early Gastric Cancer', as a set of basic guidelines in accordance with the principles of evidence-based medicine. These Guidelines cover the present state of knowledge and are divided into the following seven categories: Indications, Preoperative diagnosis, Techniques, Evaluation of curability, Complications, Long-term postoperative surveillance, and Histology. Twenty-three statements were finally accepted as guidelines, and the majority of these were obtained from descriptive studies with lower evidence levels. A number of statements had to be created by consensus (the lowest evidence level), as evidence levels remain low for many specific areas in this field.

Novel method for the management of stenosis after gastric endoscopic submucosal dissection: mucosal incision with steroid injection contralateral to the severely contracted scar

The aim of the present report was to investigate the efficacy of local steroid injection and oral administration contralateral to a severe contracted scar of large endoscopic submucosal dissection (ESD) for gastric cancer. Among 254 cases that underwent gastric ESD, seven patients underwent resection of more than three-quarters of the circumference of the stomach. Two patients were excluded because they did not meet curative resection criteria of Japan Gastroenterological Endoscopy Society. Therefore, in five patients, circumferentiality, symptom appearance period, and weight loss period were examined. Effect of a contralateral normal mucosa incision for releasing the stenosis followed by local injection and oral steroids were also examined. Abdominal bloating, vomiting, and loss of appetite appeared 42 days on average after gastric ESD, whereas weight loss >5 kg was observed an average of 52.6 days after gastric ESD. Average contralateral mucosal incision length was 51 mm, whereas the average mucosal incision width was 31 mm. All patients underwent a mucosal incision and were given a local injection of 100 mg triamcinolone acetonide. Two patients received an additional 20 mg oral steroid. In cases combined with oral steroid, there was no re-stenosis after the mucosal incision, but two to three balloon dilatations were necessary in three cases in which oral steroids were not given. This method is considered useful for stenosis after large ESD for gastric cancer.

Unavoidable human errors of tumor size measurement during specimen attachment after endoscopic resection: a clinical prospective study

Objective

Objective evaluation of resected specimen and tumor size is critical because the tumor diameter after endoscopic submucosal dissection affects therapeutic strategies. In this study, we investigated whether the true tumor diameter of gastrointestinal cancer specimens measured by flexible endoscopy is subjective by testing whether the specimen is correctly attached to the specimen board after endoscopic submucosal dissection resection and whether the size differs depending on the endoscopist who attached the specimen.

Methods

Seventy-two patients diagnosed with early gastric cancer who satisfied the endoscopic submucosal dissection expanded-indication guideline were enrolled. Three endoscopists were randomly selected before every endoscopic submucosal dissection. Each endoscopist separately attached the same resected specimen, measured the maximum resection diameter and tumor size, and removed the lesion from the attachment board.

Results

The resected specimen diameters of the 3 endoscopists were 44.5±13.9 mm (95% Confidence Interval (CI): 23–67), 37.4±12.0 mm (95% CI: 18–60), and 41.1±13.3 mm (95% CI: 20–63) mm. Comparison among 3 groups (Kruskal Wallis H- test), there were significant differences (H = 6.397, P = 0.040), and recorded tumor sizes were 38.3±13.1 mm (95% CI: 16–67), 31.1±11.2 mm (95% CI: 12.5–53.3), and 34.8±12.8 (95% CI: 11.5–62.3) mm. Comparison among 3 groups, there were significant differences (H = 6.917, P = 0.031).

Conclusions

Human errors regarding the size of attached resected specimens are unavoidable, but it cannot be ignored because it affects the patient’s additional treatment and/or surgical intervention. We must develop a more precise methodology to obtain accurate tumor size.

Trial Registration

University hospital Medical Information Network UMIN No. 000012915

Adverse events associated with endoscopic dilation for gastric stenosis after endoscopic submucosal dissection for early gastric cancer

BACKGROUND

Gastric stenosis is a major problem after endoscopic submucosal dissection (ESD) for large early gastric cancer, but little is known about the incidence of adverse events associated with endoscopic dilation (ED) for stenosis caused by gastric ESD. The aims of this study were to determine the incidence and risk of bleeding and perforation associated with ED for gastric stenosis after ESD.

METHODS

This was a single-center, retrospective cohort study conducted at a specialized center for treating cancer. A total of 342 procedures of wire-guided balloon ED were performed for stenosis after gastric ESD in 64 patients. The incidence of adverse events and related clinical characteristics was analyzed.

RESULTS

The incidence of bleeding was 3.1% (2/64) per patient and 0.6% (2/342) per procedure. One bleeding case with incomplete cessation of antithrombotics before ED required blood transfusion. The incidence of perforation was 7.8% (5/64) per patient and 1.5% (5/342) per procedure. All perforations occurred in the lower part of the stomach. Two of the five perforation cases were inappropriate for nonoperative therapy, and thus, emergency surgery was performed. Among the other three perforation cases, one case required surgery for refractory stenosis and ED was continued in one case after nonoperative therapy.

CONCLUSIONS

The incidence of bleeding caused by ED for gastric stenosis after ESD was small. Although not significant, ED in the lower stomach presents a substantial risk of perforation.

Clinical outcomes of endoscopic resection for gastric neoplasms in the pylorus

BACKGROUND

Endoscopic resection for gastric neoplasms in the pylorus is a technically difficult procedure. We investigated clinical outcomes to determine the feasibility and effectiveness of endoscopic resection for gastric neoplasms in the pylorus.

METHODS

Subjects who underwent endoscopic resection for gastric neoplasms in the pylorus between January 1997 and February 2012 were eligible.

RESULTS

A total of 227 subjects underwent endoscopic resection for 228 gastric adenomas and early cancers in the pylorus. En bloc resection was achieved for 193 lesions (84.6%), including complete resection of 195 lesions (85.5%), and curative resection of 167 lesions (73.2%). Complete resection and curative resection rates were significantly different according to the location (prepyloric, pyloric, and postpyloric, P = 0.002 and P = 0.006). Delayed bleeding and stricture occurred in 5.3 and 3.1%, respectively, and there was no patient with perforation. During a median follow-up period of 79.0 months, local tumor recurrence was detected in 2.6%.

CONCLUSIONS

Endoscopic resection appears to be a feasible and effective method for the treatment of pyloric neoplasms, regardless of the location and distribution of tumor. Thorough evaluation of the distal margin of the tumors is necessary when tumors involve or extend beyond the pyloric ring, and the appropriate use of additional techniques may be useful.

Clinical outcomes of endoscopic submucosal dissection for early stage esophagogastric junction cancer: a systematic review and meta-analysis

BACKGROUND

Although endoscopic submucosal dissection has become widely used for the management of selected cases of early gastric cancer, the effects of endoscopic submucosal dissection for esophagogastric junction cancer have not been fully evaluated.

METHODS

Medline, Embase, and the Cochrane Library were searched using the primary keywords "endoscopic submucosal dissection," "ESD," "endoscopic resection," "esophagogastric junction," "gastroesophageal junction," and "Barrett." Six short-term clinical outcomes and three long-term oncologic outcomes were extracted.

RESULTS

A total of six studies provided data on 359 early stage esophagogastric junction cancers treated with endoscopic submucosal dissection. The pooled estimate of en bloc resection and complete resection was 98.6% (95% confidence interval 95.9-99.6%) and 87.0% (95% confidence interval 79.7-92.0%), respectively. The pooled estimate of stenosis was 6.9% (95% confidence interval 3.2-14.0%). In 269 lesions with curative resection, there was no local recurrence or distant metastasis. In contrast, three local recurrences and two distant metastases occurred in 90 lesions with non-curative resection.

CONCLUSIONS

Endoscopic submucosal dissection for early stage esophagogastric junction cancer is a feasible treatment option with high en bloc resection, complete resection rates and an acceptable range of complications. When curative resections are achieved, good oncologic outcomes are likely in the management of early stage esophagogastric junction cancer by endoscopic submucosal dissection.

Stricture occurring after endoscopic submucosal dissection for esophageal and gastric tumors

Endoscopic submucosal dissection (ESD) is a widely accepted treatment for early gastric and esophageal cancer. Compared to endoscopic mucosal resection, ESD has the advantage of enabling en bloc removal of tumors regardless of their size. However, ESD can result in a large artificial ulcer, which may lead to a considerable deformity. Circumferential mucosal defects of more than three-fourths the esophageal circumference, long longitudinal mucosal defects (>30 mm), and lesions in the upper esophagus are significant risk factors for the development of post-ESD strictures of the esophagus. In the stomach, a circumferential mucosal defects more than three-fourths in extent and longitudinal mucosal defects >5 cm are risk factors of post-ESD stricture. If scheduled early, regular endoscopic balloon dilation is effective in controlling and preventing post-ESD stricture. Moreover, intralesional steroid injections or oral steroids can achieve remission of dysphagia or reduce the need for repeated endoscopic balloon dilation. However, further study is needed to improve the prevention of stricture formation.

Oral prednisolone and triamcinolone injection for gastric stricture after endoscopic submucosal dissection

BACKGROUND

The expansion of the indications for endoscopic submucosal dissection (ESD) to include early gastric cancers has enabled extensive resection. However, post-ESD stenosis after large resections applied to the gastric cardia or pylorus is often difficult to manage. The aim of this study was to evaluate the benefit of oral prednisolone and triamcinolone injection for stenosis after gastric ESD.

METHODS

Eight patients who underwent ESD for large neoplastic lesions that extended more than three-fourths of the luminal circumference were enrolled in this study. Four patients underwent ESD for gastric cardia cancer, and four patients were treated for pyloric lesions. To prevent post-ESD stricture, oral prednisolone was started at 30 mg daily on the second day after ESD and then tapered gradually in two cases, while topical injection of 80 mg triamcinolone was performed once immediately after ESD in six cases. Endoscopic balloon dilatation (EBD) was used for stricture-related symptoms or signs including nausea, vomiting, or food residuals observed on endoscopy. EBD was also applied if a 10-mm-diameter endoscope was not able to pass through the lumen. The incidence of stenosis, the frequency and period required for EBD, the duration required for ulcer healing after ESD, and the incidences of post-procedural bleeding and perforation were assessed.

RESULTS

One of the eight patients had post-ESD stenosis requiring EBD. The median ulcer healing period after ESD was 87.5 (range, 56-133) days. No patients experienced post-procedural bleeding or perforation. There were no adverse events due to steroid therapy.

CONCLUSIONS

The results of the present study showed the safety and usefulness of steroid therapy for management of stenosis after large ESD in the gastric cardia or pylorus.

Endoscopic submucosal dissection for superficial esophageal cancer with near-circumferential lesions: our experience with 40 patients

BACKGROUND

Nowadays, there are few reports indicating whether early esophageal cancers (EsC) with near-circumferential lesions are still appropriate for the endoscopic submucosal dissection (ESD) procedure.

METHODS

Between November 2009 and December 2013, a total of 40 patients with early esophageal cancers were treated with ESD. The characteristics of the patients, the ESD procedure variables, the rates of en bloc resection, and the major complications were evaluated. The outcomes listed were reliably followed up, and postoperative endoscopic balloon dilation was conducted to treat the esophageal strictures.

RESULTS

A total of 40 patients with superficial esophageal cancers were treated with ESD procedure. The extent of the lesions as a proportion of the whole circumference of the esophageal lumen ranged from three-quarters (18/40) to four-fifths (4/40) and complete circumference (18/40). The median longitudinal diameter of the lesions was 50 mm. The median procedure time was 92.5 min (range, 70-125 min). The en bloc resection rate was 100 % (40/40). Immediate bleeding, perforation, and postoperative stenosis were noted in 7.5 (3/40), 7.5 (3/40), and 45 % (18/40) of the patients. The median number of endoscopic balloon dilations (EBDs) was 4 (range 1-14). Additional surgical treatment was performed in 2 cases, and local recurrence was detected in 1 patient (2.5 %). 2 patients (5 %) died of EsC 3 months after ESD.

CONCLUSIONS

These data will greatly expand the criteria for the use of ESD in esophageal cancer and increase the number of patients eligible for endoscopic treatment and the acceptance of the ESD procedure.

Complications related to gastric endoscopic submucosal dissection and their managements

Endoscopic submucosal dissection (ESD) for early gastric cancer is a well-established procedure with the advantage of resection in an en bloc fashion, regardless of the size, shape, coexisting ulcer, and location of the lesion. However, gastric ESD is a more difficult and meticulous technique, and also requires a longer procedure time, than conventional endoscopic mucosal resection. These factors naturally increase the risk of various complications. The two most common complications accompanying gastric ESD are bleeding and perforation. These complications are known to occur both intraoperatively and postoperatively. However, there are other rare but serious complications related to gastric ESD, including aspiration pneumonia, stenosis, venous thromboembolism, and air embolism. Endoscopists should have sufficient knowledge about such complications and be prepared to deal with them appropriately, as successful management of complications is necessary for the successful completion of the entire ESD procedure.

Gastric obstruction after endoscopic submucosal dissection

BACKGROUND

Bleeding and perforation are two major complications of gastric endoscopic submucosal dissection (ESD). There are only a few reports concerning gastric obstruction related to ESD in the stomach.

OBJECTIVE

The aim of this study was to clarify the clinicopathological features of patients who experienced gastric obstruction after gastric ESD.

METHODS

Clinicopathological data of 1878 patients who underwent gastric ESD from September 2002 to December 2010 were retrospectively reviewed. Data of lesion location, circumference, circumferential extent of ESD ulcer, specimen diameter, depth of cancer, ulcer findings within the lesion, curability of ESD, number of simultaneous lesions, and occurrence of post-operative bleeding and perforation were collected. The risk of gastric obstruction regarding lesion and procedure related factors were assessed, and treatment for these patients was studied.

RESULTS

Gastric obstruction was observed in 2.5% of the patients (47/1878). Symptoms occurred in a median of 24 days after ESD. The incidence among patients with lesions in the upper part of the stomach was 4.7% (17/316), 0.36% (3/818) in the middle, and 3.8% (27/699) in the lower part. In relation to the circumferential extent, the incidence was 50% (33/66) among patients with a resection of >75% of the circumference. Stenosis was observed in 87% (41/47) of patients with gastric obstruction. Endoscopic balloon dilation was performed in 45 patients. Perforation due to EBD occurred in four patients; one was referred to surgery.

CONCLUSIONS

Patients with a wide resection of >75% of the circumference should be considered for early repeat endoscopy after ESD, and dilation should be performed with caution if found to have stenosis.

Factors predictive of inaccurate determination of horizontal extent of intestinal-type early gastric cancers during endoscopic submucosal dissection: a retrospective analysis

BACKGROUND

Certain tumor characteristics may pose challenges when endoscopically determining the horizontal extent of early gastric cancers (EGC). In the present study, clinicopathological features related to inaccurate endoscopic evaluation of horizontal extent of intestinal-type EGC were analyzed.

PATIENTS AND METHODS

We analyzed 431 lesions with intestinal-type EGC treated by endoscopic submucosal dissection (ESD) at our hospital. We focused on whether pretreatment demarcation was accurate by comparing positional relationships between marking dots and tumor edges in resected specimens, and factors related to inaccurate evaluation were analyzed. Gender, age, tumor size, location, circumference, depth, ulceration, macroscopic type, presence of a flat (0-IIb) component, predominant histological type, mixture of diffuse-type adenocarcinoma, mixed histology, and use of magnification endoscopy with narrow band imaging were analyzed. Reasons for inaccurate evaluation were also investigated by re-examining endoscopic images and prepared histological slides.

RESULTS

Rate of inaccurate evaluation of horizontal extent was 7.4% (32/431 lesions). Multivariate analysis revealed the following significant independent variables contributing to inaccurate endoscopic evaluation: presence of a flat component, large size, and predominant histological findings of moderately differentiated adenocarcinoma. Re-examination of prepared histological slides of inaccurately evaluated cases revealed a marginal flat spreading area in 28 of the 32 lesions (87.5%). In 14 of the 32 lesions (43.8%), tumor margins were composed of moderately differentiated adenocarcinoma.

CONCLUSIONS

For lesions with a flat component, large lesions, and moderately differentiated adenocarcinoma, determination of the horizontal extent can be challenging in EGC indicated for ESD, even with the best available endoscopic tools.

Outcomes of balloon dilation for the treatment of strictures after endoscopic submucosal dissection compared with peptic strictures

BACKGROUND

The outcomes of balloon dilation for the treatment of strictures caused by endoscopic submucosal dissection (ESD) have not been evaluated previously. This study was designed to evaluate and compare the effectiveness and complications of balloon dilation for post-ESD strictures and peptic strictures.

METHODS

The medical records of 14 patients with post-ESD strictures and 48 patients with peptic strictures who underwent fluoroscopically or endoscopically guided balloon dilation between January 1997 and April 2011 at the Asan Medical Center in Korea were reviewed retrospectively.

RESULTS

The technical success rates (defined as successful dilation without major complications) of the post-ESD and peptic stricture groups were 92.9% (13/14) and 93.8% (45/48), respectively (p = 1.000). For the post-ESD and peptic stricture groups, the clinical success rates (defined as symptom improvement, as determined by the patient) at 1 month were 92.9% (13/14) and 83.3% (40/48), respectively (p = 0.67). Their clinical success rates at 6 months were 71.4% (10/14) and 70 % (28/40), respectively (p = 1.000). The mean weight gains of the post-ESD stricture group 1 and 6 months after balloon dilation were 1.1 and 4.8 kg, respectively, whereas the peptic group gained 1.4 and 3.4 kg, respectively (p = 0.814). All complications were perforations. The complication rates of the post-ESD and peptic stricture groups were 7.1 % (1/14) and 10.5 % (5/48), respectively (p = 1.000).

CONCLUSIONS

Balloon dilation is an effective and safe treatment for post-ESD strictures.

Complications of gastric endoscopic submucosal dissection

Endoscopic resection is now a widely accepted treatment for early gastric cancer, having a negligible risk of lymph-node metastasis. Endoscopic submucosal dissection (ESD) is a relatively new endoscopic resection method developed in the mid-1990 s that facilitates en-bloc resection even in patients with large or ulcerative lesions difficult to resect using conventional endoscopic mucosal resection (EMR). However, compared to EMR, ESD requires a longer procedure time and a higher level of technical expertise, in addition to having a slightly greater risk of complications. Endoscopists must be aware of not only the risk factors for, and incidence of, complications, but also how to effectively treat such complications. Perforation and bleeding are the major complications associated with gastric ESD. The perforation and delayed bleeding rates have been reported to range from 1.2% to 5.2% and 0% to 15.6%, respectively, and can usually be managed with appropriate endoscopic treatment. Immediate bleeding during gastric ESD is quite common and controlling such bleeding, which is primarily achieved by carrying out electrocautery, plays a critical role in the successful completion of ESD.