Different healing process of esophageal large mucosal defects by endoscopic mucosal dissection between with and without steroid injection in an animal model

Clinical outcomes of drug-coated balloons dilatation for benign esophageal stricture

BACKGROUND

Drug-coated balloons (DCBs) angioplasty is safe and effective for coronary artery disease. However, DCBs dilatation for the treatment of benign esophageal strictures is rarely reported.

PURPOSE

We aimed to report the clinical outcomes of DCBs dilatation for patients with benign esophageal strictures.

METHODS

From May 2020 to August 2023, 18 patients underwent DCBs dilatation for benign esophageal strictures. Baseline demographics were recorded and evaluated, including gender, age, comorbidities, stricture diameter and length, dilatation session, complications.

RESULTS

A total of 24 dilatation sessions of DCBs were performed, with a mean of 1.3 ± 0.6 sessions per patients (range 1.0-5.0). Dysphagia score decreased significantly after DCBs dilatation (2.6 ± 1.1 vs. 0.9 ± 1.3, p = 0.0002). Both stricture diameter and stricture index decreased significantly after DCBs dilatation (p < 0.0001). No procedure-related death, massive bleeding or esophageal perforation was observed during or after DCBs dilatation. Minor complications were found in only 3 patients (16.7%). All 18 patients were successfully followed up for a median period of 12.0 months. By the end of follow up, 10 patients showed no dysphagia, 6 patients showed mild dysphagia and 2 patients showed no improvement in dysphagia. The clinical success rate of DCBs dilatation is 88.9%.

CONCLUSION

DCBs dilatation may be a safe, effective and feasible treatment for benign esophageal strictures, and can be utilized as an alternative option after standard dilatation has failed. Prospective studies with large samples are needed to further validate its clinical efficacy.

Efficacy of different steroid therapies in preventing esophageal stricture after endoscopic submucosal dissection: a comparative meta-analysis

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is currently the standard therapy for superficial esophageal cancer (SEC). However, postoperative mucosal defects often lead to esophageal stricture. Although steroid application is effective prophylaxis, the efficacy and safety of various steroid administration modes remain unclear. Thus, this study aimed to evaluate the efficacy and safety of different steroid administrations for SEC patients after ESD.

METHODS

A search for relevant studies was conducted on China National Knowledge Infrastructure, Wanfang Database, PubMed, Embase, and Web of Science up to March 25, 2024. Treatment strategies were categorized into 4 groups: no prevention as control (CON), steroid injection (SI), oral steroid (OS), and SI combined with OS (SI+OS). A comparative meta-analysis was conducted to assess outcomes, including postoperative esophageal stricture rate and the number of endoscopic balloon dilation (EBD) sessions required after stricture.

RESULTS

A total of 25 studies, involving 1555 patients, were included. The surface under the cumulative rankings were as follows: SI+OS (98.9%) > OS (59.9%) > SI (41.2%) > CON (0.0%) in preventing postoperative esophageal stricture, and OS (76.9%) > SI+OS (62.1%) > SI (61.0%) > CON (0.0%) in the number of EBD sessions required. Forest plot results indicated that compared with the nonsteroid group, steroid interventions were associated with lower rates of postoperative stricture and fewer EBD sessions. Additionally, SI+OS was superior to SI or OS alone in preventing stricture, with no significant differences observed between different steroid administrations in terms of EBD sessions. The incidence of adverse reactions was <10% for all interventions, mostly mild and resolvable upon discontinuation.

CONCLUSION

This study suggests that combined administration appears preferable for preventing esophageal stricture in patients after ESD and that steroids could enhance stricture prognosis. However, owing to the lack of large-sample randomized controlled trials comparing different steroid administrations, more high-quality research is necessary to confirm these findings in the future.

Association of local steroid injection as a risk factor for electrocoagulation syndrome after esophageal endoscopic submucosal dissection

BACKGROUND

Postendoscopic submucosal dissection electrocoagulation syndrome (PEECS) is commonly observed after performing endoscopic submucosal dissection (ESD) for esophageal neoplasia. However, data on the incidence and risk factors for PEECS in the esophagus are lacking due to an unclear definition of PEECS and varied clinical settings. Therefore, we aimed to determine the risk factors for PEECS in patients undergoing ESD for esophageal neoplasia.

METHODS

We retrospectively reviewed data of relevant clinical and endoscopy-specific parameters from 202 consecutive patients with esophageal neoplasias (139 carcinomas and 63 dysplasias) who underwent ESD under general anesthesia. Esophageal PEECS was defined by satisfying at least two of the following criteria: fever ≥ 37.8 °C, leukocytosis ≥ 10,800/mm3, and localized chest pain ≥ 5/10 points as assessed on a numeric rating scale within 24 h after ESD. Significant factors associated with PEECS were determined by regression analysis.

RESULTS

PEECS was recorded in 98 of 202 (48.5%) patients. Patients with PEECS exhibited a larger tumor size (25.0 vs. 17.0 mm, P = 0.002), longer procedure (40.0 vs. 29.5 min, P = 0.021) and hemostasis times (5.0 vs. 3.5 min, P = 0.004), required greater submucosal injection volume (60.0 mL vs. 50.0 mL, P = 0.030), and had a lower rate of local steroid injection (4.1% vs. 12.5%, P = 0.029) than those without PEECS. Multivariate regression analysis revealed tumor size ≥ 17 mm (P = 0.047), procedure time ≥ 33 min (P = 0.027), and hemostasis time ≥ 5 min (P = 0.007) as risk factors for PEECS. In addition, local steroid injection was a significant negatively associated factor (P = 0.001).

CONCLUSIONS

Patients with a large tumor, prolonged procedure and hemostasis times are at a high risk of PEECS occurrence. Further, local steroid injection is a negatively associated factor.

β-elemene alleviates esophageal fibrosis after endoscopic submucosal dissection via the FAP-mediated PTEN-PI3K/AKT signaling pathway

Esophageal stricture caused by fibrosis is a serious complication after esophageal Endoscopic submucosal dissection (ESD). Myofibroblasts play a crucial role in esophageal fibrosis, so inhibiting activated myofibroblasts is a promising approach for treating esophageal fibrosis. β-Elemene, a natural product with anti-tumor and anti-fibrotic properties, has not been thoroughly examined in esophageal fibrosis. Additionally, fibroblast activation protein (FAP) and PTEN-PI3K/AKT signaling pathway are both notably linked to fibrotic diseases. Therefore, we investigated the potential mechanisms of β-elemene in esophageal fibrosis by treating primary human esophageal granulation fibroblasts (PHEGFs) with gradient concentrations of β-elemene. Our findings demonstrated that β-elemene inhibited the activity of PHEGFs in a dose-dependent manner, accompanied by downregulation of FAP, p-PI3K, and p-AKT protein expression, along with upregulation of p-PTEN protein expression. In addition, we substantiated the potential correlation between FAP and the PTEN-PI3K/AKT signaling pathway by establishing models of FAP overexpression and silencing. These results provide a new perspective on the potential mechanism of β-elemene in relieving esophageal fibrosis and offer novel therapeutic strategies for managing post-esophageal ESD stricture in clinical practice.

Self-expandable metallic stents may be more efficient than balloon dilatation alone for esophageal stricture after circumferential endoscopic submucosal dissection: a retrospective cohort study in China

INTRODUCTION

Self-expandable metallic stents (SEMSs) can be used to treat esophageal stricture after circumferential endoscopic submucosal dissection (ESD), but its efficacy and placement timing remain to be determined. In this study, the treatment time and number of dilatations were compared between the SEMS placement group and the balloon dilatation (BD) group to clarify the efficacy and placement time of SEMSs in the treatment of esophageal stricture after circumferential esophageal ESD.

METHODS

This was a retrospective cohort study. Patients with esophageal stricture after circumferential ESD between January 2015 and January 2020 were included. Data on the patients' demographic characteristics, esophageal lesion-related factors, esophageal stricture occurrence, and measures taken to treat the stricture were collected. The primary outcome was the treatment time, and the secondary outcome was the number of dilatations.

RESULTS

The total number of dilatations was 30 in the SEMS group and 106 in the BD group. The average number of dilatations in the SEMS group (1.76 ± 1.64) was significantly lower than that in the BD group (4.42 ± 5.32) (P = 0.016). Among the patients who underwent SEMS placement first had a shorter treatment time (average 119 days) than those who underwent BD first (average 245 days) (P = 0.041), and the average number of dilatations inpatients who underwent SEMS placement first (0.71 ± 1.07) was significantly lower than that in the patients who underwent BD first (2.5 ± 1.54).

CONCLUSION

SEMSs were more efficient in the treatment of esophageal stricture in a cohort of patients after circumferential esophageal ESD.

Research on triamcinolone-loaded thermosensitive chitosan hydrogels for preventing esophageal stricture induced by endoscopic submucosal dissection

Early-stage esophageal cancer is primarily treated by endoscopic submucosal dissection (ESD). However, extensive mucosal dissection creates a significant risk of postoperative esophageal stricture. Clinically, postoperative stricture can be prevented by glucocorticoids; however, there are drawbacks to both systemic and local administration of glucocorticoids, and improving drug administration methods is crucial. In this study, we developed a chitosan-based thermosensitive hydrogel for triamcinolone (TA) delivery. Our results indicated that the hydrogel remains liquid at low temperatures and can be injected into the esophageal wound site through an endoscopic biopsy channel. Upon reaching body temperature, the hydrogel undergoes spontaneous gelation and firmly adheres to the wound surface. The liquid phase enables convenient and precise delivery, while the gel phase achieves remarkable adhesion, tensile strength, and resistance to degradation. Moreover, the hydrogel exhibited an extended release duration of >10 days when loaded with a 10 mg dose. In vitro studies revealed that the hydrogel suppresses the proliferation and fibrogenesis of human scar fibroblasts (HKF). In a rat skin dermal defect model, the hydrogel attenuated keloid formation during the healing process. Consequently, the chitosan-based thermosensitive hydrogel developed in this study for triamcinolone delivery may be an effective tool for preventing post-ESD esophageal stricture.

A Novel Rat Model to Simulate the Benign Esophageal Stricture Induced by Endoscopic Submucosal Dissection

Objective

This study aimed to establish a rat model that simulates benign esophageal strictures induced by endoscopic submucosal dissection (ESD).

Materials and Methods

Sixteen male Sprague-Dawley rats were randomly divided into mucosal resection (n = 8) and sham-operated groups (n = 8). The rats in the mucosal resection group underwent a 5-mm three-fourths mucosal resection by way of a 3-mm incision in the distal esophagus under direct visualization via laparotomy. Rats in the sham-operated group underwent a 3-mm incision of the muscularis propria layer in the distal esophagus via laparotomy without mucosal resection. Dysphagia score, weight gain, mucosal constriction rate, and histology were evaluated 2 weeks after surgery.

Results

Technical success was achieved in all the animals. One rat in the mucosal resection group died of infection, and no other complications were observed. Weight gain (P < 0.001) and luminal diameter derived from the esophagograms (P < 0.001) were significantly lower in the mucosal resection group than those in the sham-operated group. Dysphagia score (P < 0.001) and mucosal constriction rate (P < 0.001) were significantly higher in the mucosal resection group than those in the sham-operated group. The inflammation grade (P = 0.002), damage to the muscularis propria (P < 0.001), number of nascent microvessels (P = 0.006), and degree of α-SMA positive deposition (P = 0.006) were significantly higher in the mucosal resection group.

Conclusion

A rat model of benign esophageal stricture induced by ESD was successfully and safely established by mucosal resection.

Risk factors for total laryngectomy associated proximal esophageal stricture formation in head and neck cancer patients

BACKGROUND

Development of esophageal strictures is common after the total laryngectomy of head and neck cancer patients. While endoscopic techniques like dilatation by balloon or Salvary bougies are well established, risk factors and pathophysiology for development of refractory strictures are less well understood.

OBJECTIVE

To evaluate risk factors associated with occurrence and recurrence of total-laryngectomy-associated esophageal strictures in head and neck cancer patients.

METHODS

We analyzed retrospectively a cohort of 170 head and neck squamous cell carcinoma patients, who underwent total laryngectomy between 2007 and 2017. The outcome measure was laryngectomy-associated proximal esophageal stricture needing an endoscopic dilatation by using a balloon or Savary dilators.

RESULTS

Of the 170 patients in the cohort, 32 (18.8%) developed strictures. Mean time between surgery and first endoscopic intervention was 24.4 months. Significant predictive factors were age ≥ 65 (p=0.017), nodal status N> 1 (p=0.003), continued alcohol abuse after surgery (p=0.005) and diabetes mellitus (p=0.005). In a subgroup, 17 of 32 patients developed refractory strictures and needed more than three dilatations to relieve dysphagia. Postoperative mean (p=0.016) and maximum (p=0.015) C-reactive protein (CRP) were predictive for refractory strictures.

CONCLUSION

Symptomatic strictures occurred in 18.8% of the cases. Age, nodal status N>1, continued alcohol abuse and diabetes mellitus were predictive factors. For refractory stenosis (>3 dilatations needed) mean and maximum postoperative CRP were predictive. This may indicate that systemic inflammatory response post-surgery is involved in the stricture formation process.

Muscular injury as an independent risk factor for esophageal stenosis after endoscopic submucosal dissection of esophageal squamous cell cancer

BACKGROUND AND AIMS

Stenosis after esophageal endoscopic submucosal dissection (ESD) has a high incidence, and muscular injury is an important risk factor for esophageal stenosis. Hence, this study aimed to classify muscular injury degrees and investigate their association with postoperative stenosis.

METHODS

This retrospective study included 1033 patients with esophageal mucosal lesions treated with ESD between August 2015 and March 2021. Demographic and clinical parameters were analyzed, and stenosis risk factors were identified using multivariate logistic regression. A novel muscular injury classification system was proposed and used to investigate the association between different muscular injury degrees and postoperative stenosis. Finally, a scoring system was established to predict muscular injury.

RESULTS

Of 1033 patients, 118 (11.4%) had esophageal stenosis. The multivariate analysis demonstrated that the history of endoscopic esophageal treatment, circumferential range, and muscular injury were significant risk factors for esophageal stenosis. Patients with type II muscular injuries tended to develop complex stenosis (n = 13 [36.1%], P < .05), and type II muscular injuries were more likely to predispose patients to severe stenosis than type I (73.3% and 92.3%, respectively). The scoring system showed that patients with high scores (3-6) were more likely to have muscular injury. The score model presented good discriminatory power in the internal validation (area under the receiver-operating characteristic curve, .706; 95% confidence interval, .645-.767) and goodness-of-fit in the Hosmer-Lemeshow test (P = .865).

CONCLUSIONS

Muscular injury was an independent risk factor for esophageal stenosis. The scoring system demonstrated good performance in predicting muscular injury during ESD.

Infigratinib, a Selective Fibroblast Growth Factor Receptor Inhibitor, Suppresses Stent-Induced Tissue Hyperplasia in a Rat Esophageal Model

PURPOSE

Stent-induced tissue hyperplasia remains a challenge for the application of self-expanding metal stents in the management of esophageal stricture. This study aimed to evaluate the efficacy of infigratinib, which is a selective fibroblast growth factor receptor inhibitor, in the prevention of stent-induced tissue hyperplasia in a rat esophageal model.

METHODS

Twenty-four male Sprague-Dawley rats underwent esophageal stent placement and were randomized to receive 1 ml of vehicle, 5 mg/kg infigratinib in 1 ml of vehicle, or 10 mg/kg infigratinib in 1 ml of vehicle via naso-gastric tube once daily for 28 days. Follow-up fluoroscopy was performed on postoperative day 28, and the stented esophageal tissues were harvested for histological and immunofluorescence examinations.

RESULTS

All rats survived until euthanasia on postoperative day 28 without procedure-related adverse events. The incidence of stent migration was 12.5%, 12.5% and 25% in the control group, the 5 mg/kg infigratinib group and, the 10 mg/kg infigratinib group, respectively. The percentage of granulation tissue area, the submucosal fibrosis thickness, the number of epithelial layers, the degree of inflammatory cell infiltration, the degree of collagen deposition, the number of fibroblast growth factor receptor 1 (FGFR1)-expressing myofibroblasts, and the number of proliferating myofibroblasts were all significantly lower in both infigratinib groups than in the control group (P < 0.05) but were not significantly different between the two infigratinib groups (P > 0.05).

CONCLUSIONS

Infigratinib significantly suppresses stent-induced tissue hyperplasia by inhibiting FGFR1-mediated myofibroblast proliferation and profibrotic activities in a rat esophageal model.

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.

Safe and Efficient Procedures and Training System for Endoscopic Submucosal Dissection

Recent improvements in endoscopists' skills and technological advances have allowed endoscopic submucosal dissection (ESD) to become a standard treatment in general hospitals. As this treatment entails a high risk of accidental perforation or hemorrhage, therapeutic procedures and training methods that enable ESD to be conducted more safely and efficiently are constantly being developed. This article reviews the therapeutic procedures and training methods used to improve the safety and efficiency of ESD and describes the ESD training system used in a Japanese university hospital at which the number of ESD procedures has gradually increased in a newly established Department of Digestive Endoscopy. During the establishment of this department, the ESD perforation rate was zero among all procedures, including those conducted by trainees.

A novel tetra-PEG based hydrogel for prevention of esophageal stricture after ESD in a porcine model

Endoscopic submucosal dissection (ESD) is an accepted treatment for early esophageal cancer and precancerous lesions, but resection of a large mucosal area often leads to postoperative esophageal stricture. Biomaterials provide a new option for the treatment of post-ESD ulcers. In this study, we developed a well-defined ammonolysis-based tetra-armed poly (ethylene glycol) (Tetra-PEG) hydrogel and investigated its efficacy and related mechanisms for preventing esophageal ESD-induced stricture in a porcine model. In terms of material properties, Tetra-PEG hydrogel present great biocompatibility，great capability to retain moisture, strong tissue adhesion and high mechanical strength. Then, six domestic female pigs were randomly divided into PEG (n = 3) and control groups (n = 3). A 3/4 of the esophageal circumference ESD was performed in all pigs. In PEG group, Tetra-PEG hydrogel was easily delivered via endoscopy and adhered to the ulcer bed tightly. Compared to control group, Tetra-PEG hydrogel accelerated esophageal ulcer healing at an early stage with enhanced epithelium regeneration, milder inflammation and lesser fibrosis by regulating TGF-β/Smad2 signaling. Taken together, our findings reveal Tetra-PEG hydrogel is a promising and attractive candidate for preventing the formation of fibrotic stricture in the process of esophageal ESD-induced ulcer repair.

Advances in the application of regenerative medicine in prevention of post-endoscopic submucosal dissection for esophageal stenosis

Endoscopic submucosal dissection (ESD) is a curative treatment for superficial esophageal cancer with distinct advantages. However, esophageal stenosis after ESD remains a tough problem, especially after large circumferential proportion of esophageal mucosa is removed, which limits the wide use of ESD, especially in circumferential lesions. In this scenario, preventive procedures are highly recommended against post-ESD esophageal stenosis. However, the efficacy and safety of traditional prophylactic methods (steroids, metal and biodegradable stents, balloon dilation, radial incision, etc.) are not satisfactory and novel strategies need to be developed. Regenerative medicine has been showing enormous potential in the reconstruction of organs including the esophagus. In this review, we aimed to describe the current status of regenerative medicine in prevention of post-ESD esophageal stenosis. Cell injection, cell sheet transplantation, and extracellular matrix implantation have been proved effective. However, numerous obstacles still exist and further studies are necessary.

Esophageal Mucosal Autograft for Preventing Stricture After Widespread Endoscopic Submucosal Dissection of Superficial Esophageal Lesions

BACKGROUND

Although esophageal mucosal autograft prevents esophageal stricture after widespread endoscopic submucosal dissec- tion and has been reported as a new technique, it is relatively unproven in clinical practice. This prospective study was conducted to evaluate our experience using esophageal mucosal autograft to prevent strictures after widespread endoscopic submucosal dissection in patients with widespread superficial esophageal lesions.

METHODS

Between October 2017 and June 2018, 15 patients with widespread superficial esophageal lesions were consecutively treated with widespread endoscopic submucosal dissection and then underwent esophageal mucosal autograft. The main outcomes measured included esophageal epithelialization and esophageal stricture.

RESULTS

The median longitudinal diameter of the widespread superficial esophageal lesions was 5.2 cm. All 15 patients were success- fully treated with widespread endoscopic submucosal dissection and esophageal mucosal autograft, and the median procedural time was 182 minutes. During follow-up (median, 23 months), esophageal epithelialization was found in 13 patients (86.7%), and 7 patients experienced esophageal stricture (46.7%). In those 7 patients, the esophageal strictures were successfully relieved after endoscopic bal- loon dilation or endoscopic radial incision. No complications related to endoscopic balloon dilation/endoscopic radial incision occurred. Additionally, local recurrence was found in 1 patient with poorly differentiated squamous cell carcinoma, and further surgical resection was performed.

CONCLUSIONS

Esophageal mucosal autograft appears to be an efficient approach to reconstructing local esophageal epithelium and might have a potential role in preventing esophageal stricture after widespread endoscopic submucosal dissection. However, as a new technique, it needs more improvement to enhance its role in preventing esophageal stricture after widespread endoscopic submucosal dissection.

Muscular injury was identified the risk factor of post-operative stenosis after large area but non-circumferential esophageal endoscopic submucosal dissection

BACKGROUND

The incidence of post-operative stenosis after esophageal Endoscopic Submucosal Dissection (ESD) ranks high. This study aimed to investigate the association between the degree of muscular injury and the incidence of post-operative stenosis.

RESEARCH DESIGN

This was a retrospective study of 133 patients with superficial esophageal lesions treated by non-circumferential ESD enrolled between January 2016 and May 2021 at two endoscopy centers. Demographic and clinical parameters were analyzed. A novel muscular injury classification system was proposed. Stenosis risk factors were identified using multivariate logistic regression. The association between the different degrees of muscular injury and the incidence of post-operative stenosis was investigated further by propensity score matching (PSM).

RESULTS

There were 133 cases evaluated in this study, 33 of which developed stenosis. Multivariate analysis suggested lesions located in the upper 1/3 of the esophagus, resections >5/6 of the circumference, and muscular injury (Grade 3 or 4 according to our proposed classification) were risk factors for stenosis. Correlation analysis suggested a positive association between the degree of muscular injury and the incidence of post-operative stenosis (r = 0.408, p < .05). For PSM, 29 stenosis cases were matched and univariate analysis further corroborated that muscular injuries of grade 3 (OR = 6.429, 95%CI = 1.318-31.367, p = .021) or 4 (OR = 7, 95%CI = 1.068-45.901, p = .043) were risk factors for stenosis.

CONCLUSION

Grade 3-4 muscular injury was identified as a risk factor of post-operative stenosis.

Stent placement to prevent strictures after esophageal endoscopic submucosal dissection: a systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) is an important method for the treatment of early esophageal cancer. However, post-procedure stenosis is one of the most common long-term complications. This meta-analysis aimed to investigate whether stent placement is effective in the stenosis prevention, and which type of stent would be more effective. A systematic and electronic search of clinical trials and observational studies conducted before March 2020 on the efficacy of stent placement in preventing esophageal stricture after ESD was performed. Search terms included "ESD," "esophageal stenosis," "esophageal stricture," and "stents." We conducted a bias risk assessment of the eligible reports and a meta-analysis of the data using Revman 5.3 software. We included two randomized controlled trials (RCTs) and a prospective cohort study involving 163 patients with esophageal mucosal defects encompassing at least three-quarters of the esophagus circumference after ESD. The meta-analysis results showed that post-ESD stenosis rates (RR, 0.37; 95% CI, 0.22-0.64; P = 0.0003) and the number of endoscopic balloon dilations (EBDs) (MD, -1.74; 95% CI, -2.46 to -1.01; P < 0.00001) were reduced in the pooled analysis of three studies, indicating that stent placement was effective for stenosis prevention, especially a polyglycolic acid (PGA) sheet combined with stent placement can prevent stenosis (RR, 0.41; 95% CI, 0.23-0.74; P = 0.003) and reduce the number of EBDs (MD, -1.65; 95% CI, -2.40 to -0.90; P < 0.0001) significantly. Stent placement can reduce the rate of esophageal stenosis after ESD, especially when stents are covered with PGA sheets. However, more high-quality, low-bias RCTs with a sufficient sample size are needed to demonstrate its effectiveness.

Impact of endoscopic submucosal dissection and epithelial cell sheet engraftment on systemic cytokine dynamics in patients with oesophageal cancer

The tumour microenvironment (TME) plays an important role in cancer development, progression, and metastasis. Various cytokines are present in the TME in oesophageal cancer. Oesophageal stricture is a major complication of endoscopic submucosal dissection (ESD) for oesophageal cancer, and inflammatory cytokines are closely related to its pathogenesis. However, the cytokine crosstalk involved in the oesophageal cancer TME and post-ESD stricture has not been fully elucidated. This study investigated the comprehensive cytokine dynamics following ESD in patients with oesophageal cancer. In addition, the effect of a novel preventive technique for post-ESD stricture, autologous cell sheet engraftment, on cytokine levels was evaluated. Various pro-inflammatory and anti-tumorigenic cytokines were elevated in patients with oesophageal cancer, and ESD transiently influenced cytokine concentrations. IL-1β and TNF-α, two major pro-inflammatory cytokines that induce oesophageal stricture, were significantly suppressed by cell sheet engraftment. In conclusion, this study revealed the distinct cytokine dynamics after ESD in patients with oesophageal cancer, together with the effect of autologous cell sheet engraftment on cytokine fluctuation. These results can accelerate research on the TME and therapeutic strategies for oesophageal cancer.

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.

A multicenter retrospective study of the esophageal triamcinolone acetonide-filling method in patients with extensive esophageal endoscopic submucosal dissection

OBJECTIVE

Endoscopic submucosal dissection (ESD) for extensive esophageal cancer is sometimes associated with post-ESD stenosis, despite preventative steroid therapy. In this retrospective multicenter analysis, we evaluated the factors associated with therapy resistance.

MATERIALS AND METHODS

We enrolled 73 patients with 75 extensive esophageal cancers treated with ESD. Stenosis prevention was performed using two esophageal triamcinolone acetonide (TA)-fillings, and repeated if stenosis was found on follow-up. Therapy-resistance factors associated with incidence of severe stenosis requiring endoscopic balloon dilation (EBD) were evaluated, including age, gender, previous treatment history, tumor location, morphology, resection size, histologic type, invasion depth, and horizontal resection grade (HR-grade 1, ≥ 9/12 and <10/12 of the circumference; grade 2, ≥ 10/12 and <11/12; grade 3, ≥ 11/12 but not circumferential; and grade 4, entirely circumferential).

RESULTS

Severe stenosis occurred in 17.3%(13/75) of cases, with a median of two EBDs (range, 1-6 times). Severe stenosis was significantly associated with HR-grade elevation and previous treatment history (p < .05); multivariate analysis showed both as independent therapy-resistance factors (p < .05). Patients without previous treatment history demonstrated severe stenosis at 12.9%(9/70): 0%(0/26) HR-grade 1, 18.8%(3/16) grade 2, 17.6%(3/17) grade 3, and 27.3%(3/11) grade 4, showing a risk of HR-grade 2 or more resection but an acceptable stenosis prevention even after entirely circumferential resection. Conversely, patients with previous treatment history demonstrated severe stenosis at a high frequency of 80%(4/5).

CONCLUSIONS

Esophageal TA-filling is a promising stenosis-preventive steroid therapy, even in entirely circumferential ESD cases. However, HR-grade 2 or more elevation and previous treatment history were independently associated with therapy resistance.

Efficacy of oral steroid gel in preventing esophageal stricture after extensive endoscopic submucosal dissection: a randomized controlled trial

BACKGROUND AND AIMS

Esophageal stricture is a distressing issue for patients with early esophageal cancer following extensive endoscopic submucosal dissection (ESD), and the current steroid-based approaches are unsatisfactory for stricture prophylaxis. We evaluated the efficacy of oral hydrocortisone sodium succinate and aluminum phosphate gel (OHA) for stricture prophylaxis after extensive ESD.

METHODS

Patients undergoing > 3/4 circumferential ESD were randomized to either the endoscopic loco-regional triamcinolone acetonide injection (ETI) plus oral prednisone group or the OHA group. The primary endpoint was incidence of esophageal stricture, and the secondary endpoints included adverse events (AEs) and endoscopic balloon dilations (EBDs).

RESULTS

The incidence of esophageal stricture in OHA group (per-protocol analysis, 9.4%, 3/32; intention-to-treat analysis, 12.1%, 4/33) was significantly less than that of control group (per-protocol analysis, 35.5%, 11/31, P = 0.013; intention-to-treat analysis, 39.4%, 13/33, P = 0.011). Two sessions of EBD were necessary to release all strictures in the OHA group, while the similar EBDs (median 2, range 1-4) for 11 of the control. Operation-related AEs included infection (control vs. OHA group = 9.7% vs. 31.3%, P = 0.034), operation-related hypokalemia (19.4% vs. 31.3%, P = 0.278), perforation (3.2% vs. 3.1%), post-ESD hemorrhage (6.5% vs. 0%), and cardiac arrhythmia (0% vs. 6.3%). Steroid-related AEs included steroid-related hypokalemia (16.1% vs. 25%) and bone fracture (3.2% vs. 0%). Multivariate logistic regression analysis demonstrated that OHA was an independent protective factor for stricture (OR 0.079; 95%CI 0.011, 0.544; P = 0.01) and mucosal defect > 11/12 circumference was an independent risk factor (OR 49.91; 95%CI 6.7, 371.83; P < 0.001).

CONCLUSIONS

OHA showed significantly better efficacy in preventing esophageal stricture after > 3/4 circumferential ESD compared to ETI plus oral prednisone.

Histological changes in the human esophagus following triamcinolone injection to prevent esophageal stricture after endoscopic submucosal dissection

BACKGROUND

Locoregional steroid injection prevents post-endoscopic submucosal dissection (ESD) esophageal stricture, but histological changes that occur following steroid injection in the human esophagus are unclear. This study investigated the histopathological characteristics caused by locoregional triamcinolone acetonide (TA) injection using human esophagectomy specimens.

METHODS

From January 2014 to December 2019, among 297 patients (373 lesions) who underwent esophageal ESD, 13 patients who underwent additional esophagectomy after ESD were examined. Seven patients (TA group) with wide excisions were injected with TA after ESD and another six patients (Non-TA group) with smaller tumors were not injected with TA. The clinical background of these patients and histopathological features of ESD ulcer scar obtained from esophagectomy specimens were retrospectively investigated.

RESULTS

The circumferential rate of ESD excision was more than three-quarters in all cases in the TA group, whereas it was less than three-quarters in the Non-TA group. No other statistical difference in the clinical background was found between the two groups. The subepithelial fibrous tissue of the ESD ulcer scar in the TA group was significantly thinner than that in the Non-TA group (P < 0.05). There was no significant difference in the thickness of the regenerated epithelium and muscularis propria layer of the ESD ulcer scar.

CONCLUSIONS

Histological finding of thinning of the subepithelial fibrous tissue of ESD ulcer scar in the human esophagus after TA injection was obtained. This suggests that TA suppresses the proliferation of the fibrous tissue of the subepithelial layer to help prevent esophageal stricture after widespread ESD in the human esophagus.

Prevention of Stricture after Endoscopic Submucosal Dissection for Superficial Esophageal Cancer: A Review of the Literature

Endoscopic resection has been the standard treatment for intramucosal esophageal cancers (ECs) because of the low risk of lymph node metastases in the lesions. In recent years, endoscopic submucosal dissection (ESD), which can resect large ECs, has been performed. However, the risk of esophageal stricture after ESD is high when the mucosal defect caused by the treatment exceeds 3/4 of the circumference of the lumen. Despite the subsequent high risk of luminal stricture, ESD has been performed even in cases of circumferential EC. In such cases, it is necessary to take measures to prevent stricture. Therefore, in this review, we aimed to clarify the current status of stricture prevention methods after esophageal ESD based on previous literature. Although various prophylactic methods have been reported to have stricture-preventing effects, steroid injection therapy and oral steroid administration are mainstream. However, in cases of circumferential EC, both steroid injection therapy and oral steroid administration cannot effectively prevent luminal stricture. To solve this issue, clinical applications, such as tissue shielding methods with polyglycolic acid sheet, autologous oral mucosal epithelial sheet transplantation, and stent placement, have been developed. However, effective prophylaxis of post-ESD mucosal defects of the esophagus is still unclear. Therefore, further studies in this research field are needed.

Effectiveness of fibrin sealant as a hemostatic technique in accelerating endoscopic submucosal dissection-induced ulcer healing and preventing stricture in the esophagus: A retrospective study

The aim of the present retrospective study was to evaluate the effectiveness of conservative electrocoagulation followed by porcine fibrin sealant (FS) as a protective hemostatic technique for wounded microvessels in promoting the healing of endoscopic submucosal dissection (ESD)-induced ulcer, and preventing esophageal strictures that follow ESD. A total of 203 patients with early esophageal cancer or precancerous lesions were retrospectively analyzed. The 1-month ulcer healing and stricture rates were compared between the two groups (combined hemostats and electrocautery groups). The 1-month complete healing rate was 77.0% in the combined hemostats group and 52.6% in the electrocautery group (P=0.003). The use of FS and a smaller resected range (<3/4 circumference) was associated with a better 1-month healing rate. For patients with a ≥3/4 circumference mucosal defect, the esophageal stricture rate was 31.6% (6/19) in the combined hemostats group and 25.0% (2/8) in the electrocautery group. There was no difference in the stricture rate (P=0.737) and dilation time (P=0.733) between the two groups. In conclusion, the application of conservative electrocoagulation followed by porcine FS as a wound-protection technique promoted ESD-induced ulcer healing in the esophagus. However, this combined hemostatic technique was not superior to the conventional hemostatic method in preventing post-ESD stricture in patients with large esophageal mucosal defects.

Prospective multicenter study of the esophageal triamcinolone acetonide-filling method in patients with subcircumferential esophageal endoscopic submucosal dissection

BACKGROUND AND AIM

The esophageal triamcinolone acetonide (TA)-filling method is a novel local approach for stenosis prevention after extensive esophageal endoscopic submucosal dissection (ESD). We evaluated this method after subcircumferential ESD.

METHODS

We enrolled 20 patients with esophageal cancer requiring subcircumferential ESD in a prospective multicenter study. Esophageal TA filling was carried out 1 day and 1 week after ESD, with follow-up endoscopy every 2 weeks. We treated severe stenosis preventing endoscope passage with endoscopic balloon dilatation (EBD) and additional TA filling, and mild stenosis allowing endoscope passage with additional TA filling only. Primary endpoint was incidence of severe stenosis; secondary endpoints were total number of EBD, rate of additional TA filling, time to stenosis and complete re-epithelialization, dysphagia score, and adverse events. Horizontal resection grade was divided into grades 1 (≥ 9/12 and <10/12 of the circumference), 2 (≥ 10/12 and <11/12), and 3 (≥ 11/12 but not circumferential) and analyzed statistically for correlation with endpoints.

RESULTS

Incidence of severe stenosis was 5.0% (1/20; 0.1-24.8%) and was treated with three EBD. Six patients showed mild stenosis. Additional TA filling was carried out in these seven patients: 0% (0/9) for grade 1 resection, 40% (2/5) for grade 2, and 83% (5/6) for grade 3 (P < 0.05). Median time to stenosis and re-epithelialization was 3 and 7 weeks, respectively. Dysphagia score deteriorated in one patient. No adverse events occurred.

CONCLUSIONS

The esophageal TA-filling method prevented stenosis after subcircumferential ESD. Grade ≥2 resection showed a high risk for stenosis, but additional TA filling for mild stenosis inhibited stenosis progression (UMIN000024384).

A Multicenter, Randomized, Controlled Trial of Rebamipide Plus Lansoprazole for the Treatment of Postendoscopic Submucosal Dissection Ulcers

To evaluate the healing efficacy of rebamipide and lansoprazole combination therapy with lansoprazole alone for endoscopic submucosal dissection (ESD)–induced ulcers and clarify the ulcer healing-associated factors.

Efficacy and safety of steroid in the prevention of esophageal stricture after endoscopic submucosal dissection: A network meta-analysis

BACKGROUND AND AIM

Even though endoscopic submucosal dissection is an important endoscopic resection technique for gastrointestinal neoplasms, there are chances that postoperative esophageal stricture might take place as a side effect. Steroid applications were reported to be effective for the prevention of stricture formation. Therefore, this study aims to evaluate the efficacy and safety of different steroid applications.

METHODS

Eligible studies published on PubMed, the Cochrane Library, Embase, Web of Science, and Chinese Biomedical Literature Database before August 2018 were reviewed. The preventions were divided as placebo/no treatment, long-term oral steroid (LOS), median-term oral steroid, short-term oral steroid, single-dose steroid injection, multiple-dose steroid injection, topical superficial steroid, steroid injection combined with oral steroid, and preemptive endoscopic balloon dilatation. The primary outcomes were postoperative esophageal stricture rate and endoscopic balloon dilatation sessions required. Complications were also analyzed.

RESULTS

A total of 19 studies were included. The network meta-results illustrated that compared with the placebo, all kinds of steroid interventions were associated with lower rates of postoperative esophageal stenosis and less number of endoscopic balloon dilatation sessions. Moreover, combined therapy was no better than single regimen therapy. No significant differences between various steroid applications in the incidence of complications were spotted during this study. Based on the results of the network and clustered ranking, LOS might be the superior prevention for postoperative stricture with satisfying efficacy.

CONCLUSION

The present study showed that LOS appears to be the optimal prevention method for postoperative stricture formation.

Efficacy of gelatin hydrogels incorporating triamcinolone acetonide for prevention of fibrosis in a mouse model

Introduction

Triamcinolone acetonide (TA), a steroid, is often used clinically to prevent dysfunctions associated with fibrosis. The objective of this study was to examine whether TA can be suspended in a gelatin sheet for tissue engineering using a mouse skin wound model.

Methods

TA was suspended in biodegradable gelatin and freeze-dried in a sheet form. The sheet was analyzed for homogeneity and controlled release of TA by high-performance liquid chromatography. We made two skin wounds on the dorsal side of mice. Gelatin sheets with TA (TA sheet) and without TA (control sheet) were attached to each skin wound. To determine the efficacy of the prepared TA sheet on the skin wounds, TA-sheet versus TA-injection experiments were conducted. Hematoxylin and eosin staining was performed to assess the grade of epithelialization and alpha smooth muscle actin (α-SMA) immunohistochemical staining was conducted to evaluate myofibroblast infiltration.

Results

In the TA-release test in vitro, 7.7 ± 2.3% of TA was released from the sheet by 24 h. After replacing the initial phosphate-buffered saline (PBS) with collagenase PBS, the amount of released TA increased over time. The wound area/original skin wound area after 15 days with the TA sheet was significantly larger than that with the control sheet (26.9 ± 5.5% vs 10.7 ± 2.6%, p = 0.023). The α-SMA positive area/whole area with the TA sheet was significantly lower than that with the control sheet (4.65 ± 0.66% vs 7.24 ± 0.7%, p = 0.023). Furthermore, the α-SMA positive area/whole area with the TA sheet was significantly lower than that with TA injection (5.32 ± 0.45% vs 7.93 ± 0.75%, p = 0.013).

Conclusions

We developed a TA sheet and confirmed both the homogeneity of the suspended TA and controlled-release of the TA in the presence of collagenase in vitro. The TA sheet caused less myofibroblast infiltration into the tissue than the control sheet or TA injection did.

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.

Roles of Steroids in Preventing Esophageal Stricture after Endoscopic Resection

BACKGROUND AND PURPOSES

Endoscopic resection has been worldwide recognized as a treatment strategy for early esophageal lesions. The occurrence of esophageal stricture after endoscopic resection will reduce the quality of life of patients. This study will evaluate the efficacy and safety of steroids in the prevention of esophageal stricture after endoscopic resection and the influence of different steroid administration methods.

METHODS

In the relevant literature database, literature from 2008 to 2018 is retrieved by using preset keywords, the search results are carefully screened, and the conclusion of the literature is synthesized to form arguments and draw conclusions.

RESULTS

73 articles met our requirements. Oral steroid administration, not prophylactic endoscopic balloon dilation alone, was effective in preventing esophagostenosis after esophagoscopic treatment and reducing the number of repeated endoscopic balloon dilations even after extensive endoscopic resection. Local steroid injection is useful and economy for preventing esophageal stricture, even though it may raise the risk of perforation during dilations. A wider range of circumferential mucosal defects is an independent predictor for stricture formation for patents given preventive steroid injections after endoscopic submucosal dissection. For complete circular mucosal defect, the further researches are essential to investigate the role of local steroid injection. The effect of other methods such as steroid gel, intravenous infusion of steroid, and novel steroid filling methods require more confirmation.

CONCLUSIONS

Therefore, steroids play an irreplaceable role in preventing esophageal stricture after endoscopic resection. Oral and local injections of steroids are the two most acceptable methods and more prospective studies are needed to compare the effectiveness and safety of these two methods.

Application of a self-assembling peptide matrix prevents esophageal stricture after circumferential endoscopic submucosal dissection in a pig model

Introduction

Circumferential endoscopic submucosal dissection (ESD) allows to treat large esophageal superficial neoplasms, however with a high occurrence of severe esophageal strictures. In a previous work, we demonstrated that the application of a prototype of self-assembling peptide (SAP) matrix on esophageal wounds after a circumferential-ESD delayed the onset of esophageal stricture in a porcine model. The aim of this work was to consolidate these results using the commercialized version of this SAP matrix currently used as a hemostatic agent.

Animals and methods

Eleven pigs underwent a 5 cm-long circumferential esophageal ESD under general anesthesia. Five pigs were used as a control group and six were treated with the SAP. In the experimental group, 3.5 mL of the SAP matrix were immediately applied on the ESD wound. Stricture rates and esophageal diameter were assessed at day 14 by endoscopy and esophagram, followed by necropsy and histological measurements of inflammation and fibrosis in the esophageal wall.

Results

At day 14, two animals in the treated group had an esophageal stricture without any symptom, while all animals in the control group had regurgitations and an esophageal stricture (33 vs. 100%, p = 0.045). In the treated group, the mean esophageal diameter at day 14 was 9.5 ± 1 mm vs. 4 ± 0.6 mm in the control group (p = 0.004). Histologically, the neoepithelium was longer in the SAP treated group vs. the control (3075 μm vs. 1155μm, p = 0.014). On immunohistochemistry, the expression of alpha smooth muscle actin was lower in the treated vs. control group.

Conclusion

Apposition of a self-assembling peptide matrix immediately after a circumferential esophageal ESD reduced by 67% the occurrence of a stricture at day 14, by promoting reepithelialization of the resected area.

Prevention of esophageal stricture after endoscopic resection

Stricture formation after esophageal endoscopic resection has a negative impact on patients' quality of life because it causes dysphagia and requires multiple endoscopic dilations. Various methods by which to prevent stricture have recently been developed and reported. Among these methods, local steroid injection is the most commonly used and is currently considered the standard method for noncircumferential resection. However, local steroid injection has a limited effect on circumferential resection. Thus, oral steroid administration is used for such cases because it may have a stronger effect than local injection. Steroid treatment, both by local injection and oral administration, is effective and low-cost; however, it may cause fragility of the esophageal wall, resulting in adverse events such as perforation during balloon dilatation. Many innovative approaches have been developed, such as tissue-shielding methods with polyglycolic acid, tissue engineering approaches with autologous oral mucosal epithelial cell sheet transplantation, and stent insertion. These methods may be promising, but they are limited by a scarcity of data. Further investigations are needed to confirm the efficacy of these methods.

Cyclodextrin Polymer Preserves Sirolimus Activity and Local Persistence for Antifibrotic Delivery over the Time Course of Wound Healing

Fibrosis and dysphagic stricture of the esophagus is a major unaddressed problem often accompanying endoscopic removal of esophageal cancers and precancerous lesions. While weekly injections of antiproliferative agents show potential for improved healing, repeated injections are unlikely clinically and may alternatively be replaced by creating an esophageal drug delivery system. Affinity-based polymers have previously shown success for continuous delivery of small molecules for weeks to months. Herein, we explored the potential of an affinity-based microparticle to provide long-term release of an antiproliferative drug, sirolimus. In molecular docking simulations and surface plasmon resonance experiments, sirolimus was found to have suitable affinity for beta-cyclodextrin, while dextran, as a low affinity control, was validated. Polymerized beta-cyclodextrin microparticles exhibited 30 consecutive days of delivery of sirolimus during in vitro release studies. In total, the polymerized beta-cyclodextrin microparticles released 36.9 mg of sirolimus per milligram of polymer after one month of incubation in vitro. Taking daily drug release aliquots and applying them to PT-K75 porcine mucosal fibroblasts, we observed that cyclodextrin microparticle delivery preserved bioactivity of sirolimus inhibiting proliferation by 27-67% and migration of fibroblasts by 28-100% of buffer treated controls in vitro. Testing for esophageal injection site losses, no significant loss was incurred under simulated saliva flow for 10 min, and 16.7% of fluorescently labeled polymerized cyclodextrin microparticle signal was retained at 28 days after submucosal injection in esophageal tissue ex vivo versus only 4% of the initial amount remaining for free dye molecules injected alone. By combining affinity-based drug delivery for continuous long-term release with a microparticle platform that is injectable yet remains localized in tissue interstitium, this combination platform demonstrates promise for preventing esophageal fibrosis and stricture.

Efficacy of triamcinolone-soaked polyglycolic acid sheet plus fully covered metal stent for preventing stricture formation after large esophageal endoscopic submucosal dissection

Esophageal stricture is a major problem for patients with large superficial esophageal squamous cell neoplasms (SESCNs) after endoscopic submucosal dissection (ESD). Although many measures could be used as prophylaxis for post-ESD strictures, a well-accepted method has not yet been established. We propose using a triamcinolone-soaked polyglycolic acid sheet plus fully covered metal stent (TS-PGA+FCMS) as a novel method to prevent stricture formation after large esophageal ESD. From June 2016 to May 2017, nine patients with SESCNs (≥3/4 of the esophageal circumference) who underwent TS-PGA+FCMS placement immediately after ESD and did not require additional surgical resection were enrolled in this case series. All stents were removed 4-6 weeks post-ESD. The sizes of mucosal defects in 9 patients were 3/4 (n = 1), 4/5 (n = 2), 1/1 (n = 6). The average size of resection was 90.0 mm (range: 60-140 mm). The incidence of stricture was 33.3% (3/9) of patients. No stricture occurred in 3 patients with noncircumferential resection, while stricture occurred in 50% (3/6) patients with circumferential resection. The median number of EBD sessions was 4 (range: 3-4 sessions). No adverse events or recurrences were observed during the median follow-up period of 15.2 months (range: 12-22 months). The TS-PGA+FCMS method is safe and may decrease the incidence of esophageal stricture and the number of EBD sessions after large esophageal ESD.

Deployment of carboxymethyl cellulose sheets to prevent esophageal stricture after full circumferential endoscopic submucosal dissection: A porcine model

BACKGROUND AND AIM

Esophageal stricture is a serious adverse event secondary to extensive endoscopic submucosal dissection (ESD). The present study aimed to investigate the efficacy of carboxymethyl cellulose (CMC) sheets for the prevention of esophageal stricture after full circumferential ESD in an animal model.

METHODS

Fourteen porcine models were randomized into a control group (n = 7) and a CMC group (n = 7). Five-centimeter-long circumferential esophageal ESD was carried out at a distance of 40 to 45 cm from the incisors in all models. In the CMC group, CMC sheets were placed over the mucosal defect completely after ESD, whereas the control group underwent routine ESD only. Endoscopic examination was conducted after the first and second week post-ESD. Esophageal specimens were harvested during post-mortem and were evaluated for macroscopic and histological appearance. Blood serum levels of four pro-inflammatory or profibrotic cytokines were measured quantitatively.

RESULTS

The CMC group had better food tolerability during the second week post-ESD. The CMC group showed a significantly lower esophageal mucosal stricture rate compared to the control group. Histological assessments showed less fibrosis in the submucosal layer, milder damage to the muscularis propria, and enhanced re-epithelization in the CMC group. Serum transforming growth factor beta 1 levels were significantly lower in the CMC group post-ESD.

CONCLUSION

Deployment of CMC sheets on the mucosal defect appears to be a promising method for preventing esophageal strictures after extensive ESD.

Effect of polyglycolic acid sheet plus esophageal stent placement in preventing esophageal stricture after endoscopic submucosal dissection in patients with early-stage esophageal cancer: A randomized, controlled trial

AIM

To assess the effect of polyglycolic acid (PGA) plus stent placement compared with stent placement alone in the prevention of post-endoscopic submucosal dissection (ESD) esophageal stricture in early-stage esophageal cancer (EC) patients.

METHODS

Seventy EC patients undergoing ESD were enrolled in this randomized, controlled study. Patients were allocated randomly at a 1:1 ratio into two groups as follows: (1) PGA plus stent group (PGA sheet-coated stent placement was performed); and (2) Stent group (only stent placement was performed). This study was registered on http://www.chictr.org.cn (No. chictr-inr-16008709).

RESULTS

The occurrence rate of esophageal stricture in the PGA plus stent group was 20.5% (n = 7), which was lower than that in the stent group (46.9%, n = 15) (P = 0.024). The mean value of esophageal stricture time was 59.6 ± 16.1 d and 70.7 ± 28.6 d in the PGA plus stent group and stent group (P = 0.174), respectively. Times of balloon dilatation in the PGA plus stent group were less than those in the stent group [4 (2-5) vs 6 (1-14), P = 0.007]. The length (P = 0.080) and diameter (P = 0.061) of esophageal strictures were numerically decreased in the PGA plus stent group, whereas no difference in location (P = 0.232) between the two groups was found. Multivariate logistic analysis suggested that PGA plus stent placement (P = 0.026) was an independent predictive factor for a lower risk of esophageal stricture, while location in the middle third (P = 0.034) and circumferential range = 1/1 (P = 0.028) could independently predict a higher risk of esophageal stricture in EC patients after ESD.

CONCLUSION

PGA plus stent placement is more effective in preventing post-ESD esophageal stricture compared with stent placement alone in EC patients with early-stage disease.

Progress on the Prevention of Esophageal Stricture after Endoscopic Submucosal Dissection

Endoscopic submucosal dissection (ESD) has been widely accepted as an effective, minimally invasive treatment for superficial esophageal cancers. However, esophageal stricture often occurs in patients with large mucosal defects after ESD. In this review, we discuss various approaches recently researched to prevent esophageal strictures after ESD. These approaches can be classified as pharmacological treatments, esophageal stent treatments, and tissue engineering approaches. Most of the preventive approaches still have their limitations and require further research. With the improvement of current therapies, ESD can be more widely utilized as a minimally invasive treatment with minimal complications.

Impact of electrosurgical unit mode on post esophageal endoscopic submucosal dissection stricture in an in vivo porcine model

BACKGROUND AND AIM

 Strictures are a major complication of esophageal endoscopic submucosal dissection (ESD) for superficial esophageal carcinoma. Post ESD, stricture develops during the process of scar formation, which is related to inflammation caused by ESD. We planned a study to evaluate whether certain electrosurgical unit modes could attenuate strictures after esophageal ESD.

METHODS

 A total of 16 ESD, three-quarters of the esophageal circumference, were performed in four live pigs. A ball-tip Flush knife was used for mucosal incision. Submucosal dissection was performed using a Hook knife in monopolar mode and a ball-tip Jet B-knife in bipolar mode. Applied electrosurgical unit modes were FORCED COAG, SWIFT COAG, SPRAY COAG, ENDO CUT in monopolar mode, and FORCED COAG in bipolar mode. One month after ESD, the pigs were killed humanely and the severity of strictures and fibrosis was assessed.

RESULTS

 The resected site in the esophagus showed complete mucosal regrowth and scar formation in all pigs. The quotients of stricture following ENDO CUT, SWIFT COAG, FORCED COAG effect2, FORCED COAG effect3, FORCED COAG effect4, SPRAY COAG, and Bipolar FORCED COAG mode were 16 %, 28 %, 38 %, 33 %, 51 %, 39 %, and 47 %, respectively. The equivalent quotients of fibrosis were 7 %, 28 %, 31 %, 30 %, 35 %, 63 %, and 100 %, respectively. ENDO CUT mode was associated with the lowest mean quotients of stricture and fibrosis.

CONCLUSION

 ENDO CUT mode showed promising results to attenuate fibrosis and strictures after esophageal ESD.

Esophageal triamcinolone acetonide-filling method: a novel procedure to prevent stenosis after extensive esophageal endoscopic submucosal dissection (with videos)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) for extensive esophageal carcinomas may cause severe stenosis requiring endoscopic balloon dilations (EBDs). A standard prevention method has not been established. We propose the esophageal triamcinolone acetonide (TA)-filling method as a novel local steroid administration procedure.

METHODS

We enrolled 22 consecutive patients with early esophageal cancer who were treated using either subcircumferential or circumferential ESD (15 and 7 procedures, respectively) in this case series. Esophageal TA filling was performed on the day after ESD and 1 week later and was performed again if mild stenosis was found on follow-up. EBD with TA filling was performed only for severe stenosis that prevented endoscope passage. The primary endpoint was the incidence of severe stenosis. Secondary endpoints were the total number of EBDs and additional TA filling, dysphagia score, time to stenosis and to complete re-epithelialization, and any adverse events.

RESULTS

The incidence of severe stenosis was 4.5% (1/22; confidence interval, .1%-22.8%), and EBD was performed 2 times in 1 patient. Mild stenosis was found in 9 patients. Additional TA filling was performed in 45.5% of patients (10/22; median, 5 times; range, 1-13). The dysphagia score deteriorated to 1 to 2 in 31.8% (7/22) but showed a final score of 0 after complete re-epithelialization in 90.9% (20/22). The median time to stenosis was 3 weeks (range, 3-4) and that to complete re-epithelialization was 7 weeks (range, 4-36). No severe adverse events occurred.

CONCLUSIONS

The esophageal TA-filling method is highly effective for preventing severe stenosis after extensive esophageal ESD.

Approaches for stricture prevention after esophageal endoscopic resection

BACKGROUND AND AIMS

Endoscopic resection of extensive esophageal lesions has become more common as endoscopic resection techniques and equipment have developed. However, extensive esophageal endoscopic resections can cause postoperative esophageal strictures, which have a negative impact on the quality of life of patients. We aimed to review current treatments and innovative approaches to prevent esophageal strictures after widespread endoscopic resection of esophageal lesions.

METHODS

We performed a comprehensive literature search from 2000 to 2016 using predetermined search terms to identify relevant articles and summarized their results as a narrative review.

RESULTS

A total of 21 original articles and case series were identified. A circumferential mucosal defect involving more than three fourths of the esophageal luminal circumference was the primary risk factor for developing an esophageal stricture after endoscopic resection. Oral and injectable steroid therapy demonstrated promise in preventing post-endoscopic submucosal dissection esophageal strictures, with both strategies significantly reducing the number of required endoscopic balloon dilations. More data are needed on prophylactic self-expandable metal stents, local botulinum toxin injection, and oral tranilast as a strategy to prevent post-endoscopic submucosal dissection esophageal strictures. Although preliminary studies of tissue-shielding resection sites with polyglycolic acid sheets and fibrin glue and autologous cell sheet transplantation have demonstrated promising results, additional larger validation studies are needed.

CONCLUSIONS

Oral and locally injected/administered steroids are first-line options for the prevention of esophageal strictures, but additional innovative solutions are being developed.

Feasibility of Short-Period, High-Dose Intravenous Methylprednisolone for Preventing Stricture after Endoscopic Submucosal Dissection for Esophageal Cancer: A Preliminary Study

OBJECTIVE

A wide mucosal defect after endoscopic submucosal dissection (ESD) for esophageal cancer is associated with increased risk of stricture. This study was conducted to evaluate the feasibility of short-period, high-dose intravenous methylprednisolone administration (steroid pulse therapy) in preventing post-ESD esophageal stricture.

METHODS

This prospective study examined 13 lesions in 11 consecutive patients with esophageal squamous cell carcinoma who underwent ESD that involved three-quarters or more of the circumference of the esophagus or who had a longitudinal resected specimen diameter of ≥5 cm. Steroid pulse therapy was initiated the day after ESD and continued for 3 consecutive days. The primary endpoint was the stricture rate after ESD. Secondary endpoints were adverse events (AEs) associated with steroid pulse therapy, time until the development of stricture, and the frequency and duration of endoscopic balloon dilation (EBD).

RESULTS

The stricture rate was 54.5% (6/11). The median time until stricture development was 15 days. The median number of EBD sessions required was 2.5. The median duration of EBD was 14.5 days. AEs related to steroid pulse therapy and postprocedure complications were not observed.

CONCLUSION

No preventive effect of the stricture after esophageal ESD by steroid pulse therapy was found, although the therapy was administered safely.

Risk of perforation in balloon dilation associated with steroid injection for preventing esophageal stricture after endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

 Endoscopic local steroid injection (LSI) has been used to prevent esophageal strictures after endoscopic submucosal dissection (ESD) for superficial esophageal neoplasms (SENs). This study aimed to evaluate the safety and efficacy of LSI therapy.

PATIENTS AND METHODS

 From May 2007 to September 2014, at four institutions, 40 consecutive patients with SENs were treated with ESD that left a mucosal defect of more than three-quarters of the esophageal circumference. Two patients who underwent esophagectomy after ESD were excluded, and 38 patients were analyzed. The incidence of post-ESD strictures and adverse events associated with LSI were retrospectively investigated.

RESULTS

 Prophylactic LSI was administered in 28 patients (LSI group), and not administered in 10 patients (Non-prevention group). Post-ESD stricture rates were significantly lower in the LSI group (43 %) than in the Non-prevention group (90 %) ( P  = 0.012). Endoscopic balloon dilation (EBD) was conducted in 11 patients (39 %) in the LSI group and in 7 (70 %) in the Non-prevention group. In the LSI group, perforation caused by EBD occurred in five patients, while in the Non-prevention group, it occurred in only one patient who had received subsequent LSI before the perforation. Four patients with perforation successfully recovered after conservative therapy, but the other two patients required surgical treatment. A review of follow-up examinations with endoscopic ultrasonography and narrow-band imaging showed impaired ulcer-healing process after LSI.

CONCLUSION

 LSI is useful for preventing post-ESD strictures, but it appears to increase the risk of perforation in cases of EBD.

Single Locoregional Triamcinolone Injection Immediately After Esophageal Endoscopic Submucosal Dissection Prevents Stricture Formation

OBJECTIVES

Although endoscopic submucosal dissection (ESD) is an efficient treatment for superficial esophageal cancer, it is associated with stricture formation after wide-circumference resection that leads to a low quality of life. Although locoregional steroid injections prevent stricture formation, a randomized comparative study did not report any advantages associated with steroid injection. We evaluated the prophylactic efficacy of a single locoregional triamcinolone injection for stricture formation after esophageal ESD.

METHODS

This was a retrospective matched case-control study using propensity score matching (PSM). Between April 2006 and July 2015, a total of 602 patients with superficial esophageal neoplasia underwent ESD. Among them, 189 patients with mucosal defects that spanned more than 2/3 of the esophageal circumference were included. After exclusion, 150 patients were enrolled. Triamcinolone acetonide (80 mg) was injected into the residual submucosal layer of the resected region immediately after ESD. PSM was performed to reduce the effects of selection bias for steroid injection. The primary outcome was the incidence of stricture formation. The secondary outcome was the number of balloon dilatation procedures required to resolve the stricture formation.

RESULTS

Thirty-seven patients, with and without triamcinolone injection each, were matched after PSM. The incidence of stricture formation decreased from 45.9% (17/37) without triamcinolone injection to 18.9% (7/37) with triamcinolone injection (p=0.016). After matching, the mean number of balloon dilatation procedures required also decreased from 2.8±4.6 to 0.6±1.5 times (P<0.01).

CONCLUSIONS

A single locoregional triamcinolone injection efficiently prevented stricture formation after esophageal ESD.