Unveiling the potential of electrocautery-enhanced lumen-apposing metal stents in endoscopic ultrasound-guided biliary drainage

Abstract

This editorial delves into Peng et al's article, published in the World Journal of Gastrointestinal Surgery. Peng et al's meta-analysis investigates the effectiveness of electrocautery-enhanced lumen-apposing metal stents (ECE-LAMS) in ultrasound-guided biliary drainage for alleviating malignant biliary obstruction. Examining 14 studies encompassing 620 participants, the research underscores a robust technical success rate of 96.7%, highlighting the efficacy of ECE-LAMS, particularly in challenging cases which have failed endoscopic retrograde cholangio pancreatography. A clinical success rate of 91.0% underscores its impact on symptom alleviation, while a reasonably tolerable adverse event rate of 17.5% is observed. However, the 7.3% re-intervention rate stresses the need for post-procedural monitoring. Subgroup analyses validate consistent outcomes, bolstering the applicability of ECE-LAMS. These findings advocate for the adoption of ECE-LAMS as an appropriate approach for biliary palliation, urging further exploration in real-world clinical contexts. They offer valuable insights for optimizing interventions targeting malignant biliary obstruction management.

Key Words: Biliary drainage; Electrocautery-enhanced lumen-apposing metal stent; Endoscopic retrograde cholangiopancreatography; Endoscopic ultrasound; Malignant biliary obstruction

Core Tip: This meta-analysis highlights the effectiveness of electrocautery-enhanced lumen-apposing metal stents (ECE-LAMS) in ultrasound-guided biliary drainage for malignant obstruction. Based on diverse studies, it demonstrates a strong technical success rate of 96.7%, showcasing ECE-LAMS' efficacy in challenging cases post-failed endoscopic retrograde cholangio pancreatography. The notably high clinical success rate underscores its impact on symptom relief, and the safety profile is deemed acceptable. However, the observed adverse events and re-intervention rate emphasize the importance of vigilant post-procedural monitoring. Consistent outcomes across subgroups enhance the applicability of ECE-LAMS, positioning it as a versatile tool for palliation in cases of malignant biliary obstruction.

INTRODUCTION

In patients with obstruction of distal biliary tree attributed to malignant etiology, endoscopic retrograde cholangio pancreatography (ERCP) is the preferred fashion for bile duct drainage. However, where ERCP fails, alternate methods need to be explored. Endoscopic ultrasound-guided-biliary drainage (EUS-BD) has turned out to be a useful option for managing malignancy-induced biliary obstruction, especially when conventional options like ERCP face challenges[1]. A significant advancement related to biliary drainage by endoscopy is the application of electrocautery-enhanced lumen-apposing metal-stents (ECE-LAMS), a technology with the potential to improve the procedural success and safety of the technique[2]. This stent allows for biliary-enteric anastomosis under endoscopic ultrasound (EUS) guidance in a single step itself, obviating the need for previous bile duct puncturing or guide-wire insertion.

In the past, surgical bypass or percutaneous trans-hepatic biliary-drainage (PTBD) was deemed to be the best method for providing palliation in case of patients in whom ERCP is found to be unsuccessful for malignant biliary obstruction. While surgical biliary bypass did demonstrate effective technical success, it was frequently associated with a significant occurrence of major adverse events and even mortality. On the other hand, PTBD, while demonstrating technical success, ended up with a high rate of complications and negatively affected health- related quality of life, with an adverse event rate reaching even up to 60%. Conventional approaches to biliary drainage, such as plastic stents and uncovered metal stents, frequently pose limitations, especially in cases of failed ERCP. ECE- LAMS, on the other hand, offers a new solution by combining the benefits of electrocautery and a lumen-apposing metallic stent design[3,4]. This amalgamation aims to enhance procedural precision, give secure apposition between the gastrointestinal and biliary walls, as well as potentially reduce the chances for adverse events.

While former studies have explored the varied aspects of EUS-BD, the specific focus on ECE-LAMS and its potential implications in endoscopic methods for biliary obstruction demand devoted attention[5]. This manuscript endeavors to extensively review the current literature, synthesizing evidence from pertinent studies, to give a nuanced understanding of the safety, efficacy and clinical mileage of ECE-LAMS in the realm of EUS-BD[6,7]. In exploring this content, it's imperative to consider studies that assess procedural success rates, clinical aspects, and any adverse events associated with ECE-LAMS. Though the existing body of literature has contributed precious insights into the broader geography of endoscopic interventions, the specific nuances of ECE-LAMS do need detailed examination[8].

This review seeks to consolidate the evidence surrounding ECE-LAMS in EUS-BD, drawing from different sets of studies that explore its operations in various clinical scenarios. The references cited herein represent a comprehensive array of exploration that delves into different elements of EUS-guided interventions, which includes the variety of stent designs, procedural variations, and comparative analyses against traditional approaches. A former systematic review has carried out a critical appraisal of published papers on EUS-guided interventions[9]. Nevertheless, the current exploration specifically focuses on the aspect of ECE-LAMS for palliating malignant biliary obstructions[10]. This is an update and improvement on the systematic review and meta-analysis which was published by the same authors in 2021[11]. In the meta-analysis, a comprehensive examination was accepted to assess the methodological strengths, pivotal findings, and practical implications picked from the named studies. Additionally, the research extended to the clinical implications of these findings, contemplating how they can be restated into real- world operations and provide guidance for medical practitioners in their decision- making processes.

KEY FINDINGS OF THE META-ANALYSIS

The meta-analysis conducted by Peng et al[10] intends to provide an updated and comprehensive evaluation of the efficacy and safety of biliary drainage through endoscopic-ultrasound guidance by employing ECE-LAMS for the alleviation of malignant biliary obstruction. The systematic review and meta-analysis adhered appropriately to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline, ensuring a proper reporting process. The search encompassed prominent databases, including PubMed, Embase, and Scopus, spanning from January 1, 2012, to May 13, 2022, in alignment with the introduction of ECE-LAMS in 2013. The search strategy employed a variety of relevant keywords and employed a comprehensive approach with an aim to capture relevant studies. Additionally, the searches were confined to human subject studies, and the inclusion criteria encompassed peer-reviewed publications in English-language journals.

This meta-analysis, incorporating data from a diverse set of studies, sheds light on crucial aspects that influence the clinical utility of this evolving technique. One notable strength shown by the meta-analysis is that they have included 14 eligible studies, involving a total of 620 participants. This extensive data pool adds to the statistical power of the findings from the analysis and provides a more robust foundation for drawing meaningful observations about the usefulness of ECE-LAMS in the setting of biliary drainage. The meta-analysis reveals a commendable pooled technical success rate at 96.7%, indicating the efficacy of ECE-LAMS in achieving effective biliary drainage in a significant number of cases. This high procedural success rate underscores the precision and reliability of the electrocautery-enhanced approach in establishing a secure connection between the gastrointestinal and biliary systems. Beyond the success of the technique itself, the clinical success rate, a crucial parameter in assessing the real-world effectiveness of the procedure, is reported at 91.0%. This finding suggests that ECE-LAMS not only accomplishes effective drainage but also contributes to meaningful clinical betterment in patients presenting with malignant biliary obstruction.

Safety is a paramount concern in any medical intervention, and the meta-analysis addresses this by reporting adverse events in 17.5% of patients. The documented adverse events contribute valuable insights into the safety profile of ECE-LAMS, allowing clinicians to weigh the benefits against potential risks in the decision-making process. Re-intervention rates, an essential aspect in evaluating the durability of the procedure, are reported at 7.3%. This moderate rate suggests that while ECE-LAMS demonstrates favorable success, a subset of patients may require further interventions. Comprehending the reasons behind re-interventions is crucial for refining the procedural approach and optimizing patient outcomes. Subgroup analyses performed in the meta-analysis demonstrate consistent results across various parameters, further contributing to the generalisability of the findings. This consistency suggests that the favorable outcomes observed with ECE-LAMS are not confined to specific patient subsets or study characteristics, reinforcing its potential as a versatile and widely applicable approach.

This research does have its own set of limitations. The absence of a consistent definition for clinical success may contribute to a medium level of heterogeneity. Also, subgroup analyses were hindered by the original study designs (incidence studies). The predominance of retrospective studies could contribute to potential selection bias also. Moreover, the exclusive reliance on tertiary referral centers limits the generalisability of findings to patients in local hospitals or lower-level facilities.

IMPLICATIONS FOR FUTURE RESEARCH AND PRACTICE

The outcomes depicted by this meta-analysis establish a robust groundwork for influencing the trajectory of future research and enhancing clinical practices. The positive results observed with ECE-LAMS underscore the need for further exploration into its long-term effectiveness, identification of optimal patient selection criteria, and potential refinements in procedural techniques. Clinicians must stay informed about the evolving evidence and actively engage in the ongoing discourse regarding the seamless integration of ECE-LAMS into routine clinical practice. This continuous involvement will not only contribute to the advancement of knowledge but also foster improved patient outcomes in the realm of biliary interventions.

CONCLUSION

In conclusion, Peng et al's meta-analysis[10] provides a comprehensive and contemporary overview of the performance of ECE-LAMS in endoscopic biliary-drainage for biliary obstruction due to malignant causes. The very good technical triumph and clinical efficacy, coupled with a relatively acceptable safety profile, are enough to place ECE-LAMS as a promising treatment modality for palliation in challenging clinical aspects. The use of ECE-LAMS proves effective and safe for cases having obstructive jaundice where ERCP is unfeasible, offering implicit generalisability among clinicians. This merits recognition as a standard element in managing difficult biliary obstruction. Further exploration, exploring ECE-LAMS as a primary intervention for biliary drainage or with a ‘bridge to surgery’ intent, is warranted to enhance practical operations with anticipated positive outcomes.