Mucosal loss as a critical factor in esophageal stricture formation after mucosal resection: a pilot experiment in a porcine model

When Stents Go Astray, We Find a Way: A Case Report on Retrieving a Migrated Esophageal Stent

Benign esophageal strictures are characterized by the narrowing of the esophageal passage due to fibrotic changes. These strictures can arise from various causes, including gastroesophageal reflux disease, which leads to peptic strictures; surgical procedures causing esophageal injury, resulting in anastomotic strictures; radiation therapy, ingestion of corrosive substances, or endoscopic resection. Approximately 10% of benign esophageal strictures do not respond to conventional dilation therapy, prompting the consideration of temporary stent insertion as an alternative treatment approach. However, only about one-third of patients with refractory benign esophageal strictures experience sustained relief from dysphagia following self-expanding stent placement. Challenges such as stent migration and hyperplastic tissue response pose limitations to the effectiveness of this intervention. The utilization of self-expanding metal stents (SEMSs) in benign esophageal diseases is not standard practice due to the associated risks of adverse events such as tissue ingrowth at the uncovered portions, migration, and bleeding. One of the major challenges encountered is the growth of hyperplastic tissue around the stent during retrieval and subsequent serial esophageal bougie dilations. Long-term self-bougie dilations, coupled with the patient's gained self-confidence, played a crucial role in the management. While most migrated esophageal metallic stents are typically left in the stomach, in this particular case, the patient's progressive dysphagia necessitated retrieval. This article discusses a 65-year-old female with a benign esophageal stricture treated with a self-expandable metallic stent. Eight months post-insertion by another doctor, she presented to us with worsening dysphagia. Endoscopy revealed a stent migrated into the antrum of the stomach with a proximal esophageal stricture. Endoscopic dilation and stent retrieval were performed, followed by serial esophageal bougie dilations. Subsequently, her dysphagia settled with self-insertion of a 9 mm esophageal dilator.

A novel modified endoscopic method for treating patients with refractory gastro-esophageal disease and moderate hiatus hernia

BACKGROUND AND AIM

endoscopic anti-reflux mucosectomy (ARMS) is effective for patients with refractory gastroesophageal reflux disease (rGERD) with small hiatus hernia. However, evidence of its applicability in patients with larger hernia sac is lacking. This study aimed to evaluate the efficiency and safety of ARMS for patients with rGERD with moderate hiatus hernia (3-5 cm) and determine the appropriate resection range.

METHODS

thirty-six patients with rGERD with moderate hiatus hernia were enrolled. They were divided into 2/3 and 3/4 circumferential mucosal resection groups. The patients received modified ARMS. The gastroesophageal reflux disease questionnaire (GERD-Q) and DeMeester scores, endoscopy, 24-h pH monitoring results and lower esophageal sphincter (LES) resting pressure were compared pre- and post-procedure. Therapeutic effects and complications of the two mucosal resection ranges were analyzed.

RESULTS

thirty-six patients were enrolled in this study, all of whom had undergone ARMS surgery with at least six-month follow-up. In the 2/3 circumferential mucosal resection group, the GERD-Q score, acid exposure time (AET) and DeMeester score improved significantly compared with those before surgery (p < 0.001). In the 3/4 circumferential mucosal resection group, the GERD-Q score, AET and DeMeeter score worsened after six months (p < 0.001), but there was no difference between the two groups (p > 0.05). In both groups, there was no significant improvement in the ratio of esophagitis grade C/D and LES resting pressure after treatment compared with the baseline values (p > 0.05), and no postoperative bleeding or perforation was observed. The incidence of postoperative esophageal stenosis in the 2/3 circumferential mucosal resection group was lower than that in the 3/4 circumferential mucosal resection group (p = 0.041).

CONCLUSION

modified ARMS is effective for patients with rGERD with moderate hiatus hernia, but it cannot significantly increase the postoperative resting pressure of the LES. The 2/3 circumferential mucosal resection can reduce the incidence of postoperative esophageal stenosis.

Benign esophageal stricture model construction and mechanism exploration

Esophageal stricture is a debilitating condition that negatively impacts patients' quality of life after undergoing endoscopic mucosal resection (EMR). Despite its significance, this disease remains underexplored due to the lack of a stable animal model. Under direct visualization with choledochoscopy, we retrogradely damaged the esophageal mucosal layer through the gastrostomy to create a rat model of esophageal stricture. The development of histological defects in the mucosal layer was assessed over a 2-week period after model induction. Then the models were evaluated using X-ray barium radiography, Hematoxylin-Eosin, Masson's trichrome, Sirius red, and Victoria blue staining, multiphoton microscopic imaging. Additionally, the molecular mechanisms of esophageal stricture were explored by conducting RNA transcriptome sequencing, PCR, immunohistochemistry, and immunofluorescence staining. We successfully established fifteen rat models of esophageal stricture by injuring the mucosal layer. In the model group, the mucosal defect initially occurs and subsequently repaired. The epithelium was absent and was plastically remodeled by collagen during the acute inflammatory phase (Day 1), proliferation phase (Day 7), anaphase of proliferation (Day 10), and plastic remodeling phase (Day 14). We observed increased expression of COL1A1, acta2, FGF, IL-1, and TGF-β1 pathway in the model group. We established a highly repeatable rat model of esophageal stricture, and our results suggest that the mucosal defect of the esophagus is a critical factor in esophageal stricture development, rather than damage to the muscularis layer. We identified Atp4b, cyp1a2, and gstk1 as potential targets for treating esophageal stricture, while the TGF-β pathway was found to play an important role in its development.

A Look into the Future of Endoscopic Submucosal Dissection and Third Space Endoscopy: The Role for Robotics and Other Innovation

Endoscopic resection has been widely applied especially in endoscopic submucosal dissection and third space endoscopy (TSE). Flexible endoluminal robotics allow performance of endoscopic submucosal dissection with exposure of the submucosal plane for precise dissection using two robotic arms. The introduction of TSE revolutionized the horizon of therapeutic endoscopy to the submucosal space beneath and beyond the mucosa. Advantages of TSE include avoidance of full thickness incision in gastrointestinal tract through the submucosal tunneling for performance of peroral endoscopic myotomy and submucosal tunneling endoscopic resection. In future, robotic-driven devices should be developed to enhance performance of complex endoluminal procedures and TSE.

A potential preventive method for scar stenosis after esophageal endoscopic mucosal resection using human amniotic epithelial cells in a porcine model

Objectives

The current methods employed for esophageal endoscopic mucosal resection (EMR) involve the risk of adverse postprocedural complications. Therefore, this study aimed to develop a new method to prevent stenosis following a resection procedure using human amniotic epithelial cells in a porcine model.

Methods

With the consent of a woman who underwent a cesarean section, amniotic epithelial cells were isolated from the amniotic membrane of the delivered placenta. Six swine were used for this study. Under general anesthesia, four EMRs using cap‐fitted microscope ulcers were performed on each porcine esophagus. Of the four ulcers, the two on the oral side were treated by injecting human amniotic epithelial (AE group) cells, and the remaining two on the anal side were left untreated (control group). One week after the procedure, the swine were sacrificed, and the ulcers were evaluated. The epithelialization rate was calculated by dividing the length of the epithelialized portion of each section by the length of the ulcer, which was determined using an optical microscope. Moreover, the mucosal thickening in each section was measured in terms of diameter.

Results

The epithelialization rate was significantly higher in the AE group than in the control group. Mucosal thickening was not significantly different between the groups.

Conclusions

Transplanting amniotic epithelial cells into the ulcer promoted ulcer epithelialization. Amniotic epithelial cell transplantation is a potential method for the management of ulcer scar stenosis following esophageal endoscopic submucosal dissection.

A reliable nomogram model for predicting esophageal stricture after endoscopic submucosal dissection

ABSTRACT

Currently, endoscopic submucosal dissection (ESD) has gradually become the diagnosis and treatment of choice for initial esophageal cancer. However, the formation of esophageal stricture after ESD is one of its important complications. In this paper, we intend to identify the risk factors of esophageal stricture to develop a nomogram model to predict the risk of esophageal stricture and validate this model.A total, 159 patients were included in this study, including 21 patients with esophageal stenosis. Multivariate analysis showed that age greater than 60 years, high neutrophil-to-lymphocyte ratio, the extent of esophageal mucosal defect greater than 1/2, and postoperative pathological type of early esophageal squamous cell carcinoma were independent risk factors for predicting esophageal stricture. We constructed a nomogram model to predict esophageal stenosis by these 4 independent predictors.The prediction performance of the model was verified by the area under the receiver operating characteristic curve, the area under the receiver operating characteristic curve of the model was 0.889, and the sensitivity and specificity were 80.00% and 91.28%, respectively, indicating that the prediction performance of the model was good; The calibration curve constructed by internal cross-validation suggested that the predicted results of the nomogram agreed well with the actual observed values.The nomogram model has a high accuracy for predicting esophageal stricture after esophageal ESD and is extremely important to reduce or avoid the occurrence of esophageal stricture. But it needs more external and prospective validation.

Risk factors of postoperative stricture after endoscopic submucosal dissection for superficial esophageal neoplasms: A meta-analysis

BACKGROUND

As larger-sized superficial esophageal neoplasms became candidates for endoscopic submucosal dissection (ESD), post-ESD esophageal stricture has inevitably developed into a significant complication during long-term follow-up.

METHOD

The PubMed, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Web of Science, as well as China National Knowledge Infrastructure, the Wanfang Database, and the Chinese Biomedical Literature Database, were searched to identify all the appropriate studies published from January 2000 through October 2019. For risk factor assessment between postoperative stricture and control groups, pooled odds ratios (OR) and weighted mean differences (WMD) estimation was done. All meta-analytical procedures were conducted by using Stata version 15.1 software.

RESULTS

The results showed that 11 studies with 2248 patients (284 structure cases and 1964 controls) were eligible for this meta-analysis. Statistical results indicated 6 substantial risk factors: lesion characteristics involving the upper third of the esophagus (OR 1.51, [1.02-2.25]), macroscopic type of IIa/IIc (OR 2.76, [1.55-4.92]), tumor depth of invasion above m1 (OR 7.47, [3.31-16.86]), and m2 (OR 12.67, [4.00-40.10]), longitudinal length (WMD 13.75 mm, [7.76-19.74]), circumferential diameter (WMD 10.87 mm, [8.13-13.60]), and circumferential range >3/4 (OR 38.17, [9.94-146.52]). Each additional 10% of the circumferential range increased the risk of stricture by 149% (OR 9282.46, [978.14-88089.35]).

CONCLUSIONS

Six risk factors were assessed to have a key role in the elevated risk levels of post-ESD esophageal stricture. The results can help doctors identify patients with increased risk and thus can guide management of the adequate period of surveillance after ESD and take available approaches of stricture prevention.

A patient-like swine model of gastrointestinal fibrotic strictures for advancing therapeutics

Gastrointestinal (GI) strictures are difficult to treat in a variety of disease processes. Currently, there are no Food and Drug Administration (FDA) approved drugs for fibrosis in the GI tract. One of the limitations to developing anti-fibrotic drugs has been the lack of a reproducible, relatively inexpensive, large animal model of fibrosis-driven luminal stricture. This study aimed to evaluate the feasibility of creating a model of luminal GI tract strictures. Argon plasma coagulation (APC) was applied circumferentially in porcine esophagi in vivo. Follow-up endoscopy (EGD) was performed at day 14 after the APC procedure. We noted high grade, benign esophageal strictures (n = 8). All 8 strictures resembled luminal GI fibrotic strictures in humans. These strictures were characterized, and then successfully dilated. A repeat EGD was performed at day 28 after the APC procedure and found evidence of recurrent, high grade, fibrotic, strictures at all 8 locations in all pigs. Pigs were sacrificed and gross and histologic analyses performed. Histologic examination showed extensive fibrosis, with significant collagen deposition in the lamina propria and submucosa, as well as extensive inflammatory infiltrates within the strictures. In conclusion, we report a porcine model of luminal GI fibrotic stricture that has the potential to assist with developing novel anti-fibrotic therapies as well as endoscopic techniques to address recurring fibrotic strictures in humans.

Current status of endoscopic submucosal tunnel dissection for treatment of superficial gastrointestinal neoplastic lesions

INTRODUCTION

With the widespread application of screening endoscopy and development of endoscopy-related instruments, more and more gastrointestinal cancers are detected in an early stage. Endoscopic resection is a preferred method for selected patients with superficial gastrointestinal neoplastic lesions, and endoscopic submucosal dissection (ESD) has become a standard method for its ability to perform en bloc resection regardless of the lesion size. ESD can be performed in a conventional or tunneling way, and the latter is termed endoscopic submucosal tunnel dissection (ESTD).

AREA COVERED

In the present review, we provided a comprehensive review on ESTD for treatment of superficial gastrointestinal neoplastic lesions. We mainly focus on technical details, safety and efficacy of ESTD for esophageal, gastric and colorectal lesions. The present review is expected to provide tips for operators who are going to perform ESTD.

EXPERT OPINION

The best indication of ESTD is large superficial esophageal neoplastic lesions (circumferential extent > 1/3 and longitudinal extent > 3 cm). Although ESTD has shown promising primary results for superficial gastric and colorectal neoplastic lesions, it is technically difficult and should be attempted only in experienced hands. Post-treatment stricture is a major concern, and preventive measures are recommended for patients with high risk of post-ESTD stricture.