Silicone-covered biodegradable magnesium stent for treating benign esophageal stricture in a rabbit model

Effectiveness of glucocorticoids in preventing esophageal stricture and predictors of stricture after esophageal ESD: 5 years of experience in a single medical center

Background

Esophageal stricture is one of the major complications after endoscopic submucosal dissection (ESD) of the esophagus. However, even with steroid prophylaxis, stenosis still occurs in up to 45% of patients. Accordingly, the aim of this study was to evaluate the efficacy and safety of steroid therapy in preventing esophageal strictures after ESD, as well as to assess the predictors of esophageal strictures after the application of steroids.

Methods

Between February 2018 and March 2023, 207 patients who underwent esophageal ESD at Southeast University Affiliated Zhongda Hospital were retrospectively enrolled. We evaluated stenosis rate, number of endoscopic dilations after ESD, the interval between the first endoscopic dilatation after ESD and explored risk factors for strictures after steroid prophylaxis.

Results

In the control group, the oral steroids group, and the combined group, the stenosis rates were 83/87 (95.4%), 44/53 (83.0%), and 56/67 (83.6%), respectively; the number of endoscopic dilations were 3.43 (±2.22), 2.34 (±2.17), and 1.52 (±1.25), respectively; the time intervals between first endoscopic dilation and ESD procedure were 38.36 (±6.87), 68.18 (±9.49), and 96.82 (±8.41) days, respectively; all these indicators were significantly better in the oral and combined groups than in the control group (p < 0.05). Multivariate analysis identified lesion circumference ≥ 5/6th and submucosal injection of solution were two independent factors on esophageal stricture formation (p < 0.05).

Conclusion

Steroid prophylaxis is effective and safe in preventing esophageal stenosis. Moreover, lesion circumference and submucosal injection of sodium hyaluronate were two independent factors on esophageal stricture formation even with steroids administration.

Predictors of stricture after endoscopic submucosal dissection of the esophagus and steroids application

BACKGROUND

Endoscopic submucosal dissection (ESD) is a reliable method to resect early esophageal cancer. Esophageal stricture is one of the major complications after ESD of the esophagus. Steroid prophylaxis for esophageal strictures, particularly local injection of triamcinolone acetonide (TA), is a relatively effective method to prevent esophageal strictures. However, even with steroid prophylaxis, stenosis still occurs in up to 45% of patients. Predicting the risk of stenosis formation after local TA injection would enable additional interventions in risky patients.

AIM

To identify the predictors of esophageal strictures after steroids application.

METHODS

Patients who underwent esophageal ESD and steroid prophylaxis and who were comprehensively assessed for lesion- and ESD-related factors at Southeast University Affiliated Zhongda Hospital between February 2018 and March 2023 were included in the study. The univariate and multivariate regression analyses were conducted to identify the predictors of stricture among patients undergoing steroid prophylaxis.

RESULTS

A total of 120 patients were included in the analysis. In the oral prednisone and oral prednisone combined with local tretinoin injection groups, the stenosis rates were 44/53 (83.0%) and 56/67 (83.6%), respectively. Among them, univariate analysis showed that the lesion circumference (P = 0.01) and submucosal injection solution (P = 0.04) showed significant correlation with the risk of stenosis formation. Logistic regression analyses were then performed using predictors that were significant in the univariate analyses and combined with known predictors from previous reports, such as additional chemoradiotherapy and tumor location. We identified a lesion circumference < 5/6 (OR = 0.19; P = 0.02) and submucosal injection of sodium hyaluronate (OR = 0.15; P = 0.03) as independent predictors of on esophageal stricture formation.

CONCLUSION

Steroid prophylaxis effectively prevents stenosis. Moreover, the lesion circumference and submucosal injection of sodium hyaluronate were independent predictors of esophageal strictures. Additional interventions should be considered in high-risk patients.

Comprehensive review of materials, applications, and future innovations in biodegradable esophageal stents

Esophageal stricture (ES) results from benign and malignant conditions, such as uncontrolled gastroesophageal reflux disease (GERD) and esophageal neoplasms. Upper gastrointestinal endoscopy is the preferred diagnostic approach for ES and its underlying causes. Stent insertion using an endoscope is a prevalent method for alleviating or treating ES. Nevertheless, the widely used self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) can result in complications such as migration and restenosis. Furthermore, they necessitate secondary extraction in cases of benign esophageal stricture (BES), rendering them unsatisfactory for clinical requirements. Over the past 3 decades, significant attention has been devoted to biodegradable materials, including synthetic polyester polymers and magnesium-based alloys, owing to their exceptional biocompatibility and biodegradability while addressing the challenges associated with recurring procedures after BES resolves. Novel esophageal stents have been developed and are undergoing experimental and clinical trials. Drug-eluting stents (DES) with drug-loading and drug-releasing capabilities are currently a research focal point, offering more efficient and precise ES treatments. Functional innovations have been investigated to optimize stent performance, including unidirectional drug-release and anti-migration features. Emerging manufacturing technologies such as three-dimensional (3D) printing and new biodegradable materials such as hydrogels have also contributed to the innovation of esophageal stents. The ultimate objective of the research and development of these materials is their clinical application in the treatment of ES and other benign conditions and the palliative treatment of malignant esophageal stricture (MES). This review aimed to offer a comprehensive overview of current biodegradable esophageal stent materials and their applications, highlight current research limitations and innovations, and offer insights into future development priorities and directions.

Pirfenidone prevents esophageal stricture by inhibiting nucleotide binding oligomerization domain like receptor protein 3 inflammasome activation

BACKGROUND AND AIM

Esophageal injury often results in a scar, leading to refractory strictures. The NLRP3 inflammasome activates caspase-1, causing the maturation of interleukin (IL)-1β. Here, we aimed to investigate the preventive effect of pirfenidone (PFD), an antifibrotic drug, on esophageal stricture after ulcer healing and studied its mechanism by focusing on the activation of the NLRP3 inflammasome.

METHODS

Esophageal ulcers were induced in rats via the local application of acetic acid in the serosa. PFD was intraperitoneally administered to the rats 3 days after ulcer induction. The effect of PFD on esophageal stricture after ulcer healing was assessed by esophagography on day 9. The protein levels of mature caspase-1 and IL-1β were assessed by western blotting.

RESULTS

The ulcers fully developed 3 days after induction and were almost scarred by day 9 with severe strictures. PFD promoted ulcer healing and attenuated fibrotic collagen in the submucosa by suppressing the increase in NLRP3, cleaved caspase-1, and mature IL-1β expression, improving stricture rate (PFD vs vehicle = 55% vs 81%). Exogenous IL-1β abolished the therapeutic effects of PFD on ulcer healing and stricture formation. Furthermore, NLRP3 and caspase-1 inhibitors mimicked the effects of PFD on ulcer healing and stricture formation, with suppression of the increase in cleaved caspase-1 and mature IL-1β proteins and expression of fibrosis-related molecules including transforming growth factor (TGF)-β1.

CONCLUSION

The NLRP3 inflammasome promotes esophageal stricture formation following ulcer healing, and PFD exerts potential prophylactic activity against strictures, possibly via the inhibition of the NLRP3/IL-1β/TGF-β1 axis.

Advances in the Prevention and Treatment of Esophageal Stricture after Endoscopic Submucosal Dissection of Early Esophageal Cancer

Endoscopic submucosal dissection (ESD) has become the main treatment for early esophageal cancer. While treating the disease, ESD may also cause postoperative esophageal stricture, which is a global issue that needs resolution. Various methods have been applied to resolve the problem, such as mechanical dilatation, glucocorticoids, anti-scarring drugs, and regenerative medicine; however, no standard treatment regimen exists. This article describes and evaluates the strengths and limitations of new and promising potential strategies for the treatment and prevention of esophageal strictures.