Endoscopic ultrasound-guided biliary drainage after failed endoscopic retrograde cholangiopancreatography: The road is open for almighty biliopancreatic endoscopists!

Abstract

Commentary on the article written and published by Peng et al, investigating the role of endoscopic ultrasound (EUS)-guided biliary drainage for palliation of malignant biliary obstruction after failed endoscopic retrograde cholangiopancreatography (ERCP). For 40 years endoscopic biliary drainage was synonymous with ERCP, and EUS was used mainly for diagnostic purposes. The advent of therapeutic EUS has revolutionized the field, especially with the development of a novel device such as electrocautery-enhanced lumen-apposing metal stents. Complete biliopancreatic endoscopists with both skills in ERCP and in interventional EUS, would be ideally suited to ensure patients the best drainage technique according to each individual situation.

Key Words: Cholestasis; Drainage; Electrocautery-enhanced lumen-apposing metal stents; Endoscopic ultrasound; Endosonography; Endoscopic retrograde cholangiopancreatography; Interventional procedures; Jaundice; Malignant; Biliary obstruction

Core Tip: Endoscopic retrograde cholangiopancreatography is still considered the most appropriate treatment for the management of biliary obstruction but endoscopic ultrasound-guided biliary drainage will be increasingly important in this patient population. Biliopancreatic endoscopists should master both endoscopic retrograde cholangiopancreatography and interventional endoscopic ultrasound in order to guarantee a comprehensive management of patients with biliary obstruction.

INTRODUCTION

Endoscopic retrograde cholangiopancreatography (ERCP) is still recommended by international guidelines as the first-line therapy for the management of malignant distal biliary obstruction (MBO)[1]. However, in clinical practice, some challenges could undermine the role of ERCP in MBO such as the inability to reach the papilla, difficult biliary cannulation and adverse events[2,3].

CHALLENGES OF ERCP IN MBO

In about 25%-45% of patients with malignant jaundice, duodenal infiltration or gastric outlet obstruction may preclude ERCP and in patients with iatrogenic altered anatomy, e.g., after surgery such as a Billroth II gastrectomy or Roux-en-Y gastric bypass, ERCP becomes much more challenging and often not feasible at all[4]. Selective biliary cannulation of a native papilla may already be challenging on its own and the failure rate can reach 15%, even in the hands of experienced endoscopists, depending on the papillary characteristics, location and periampullary findings (such as diverticulum, lipoma, duplication cyst)[5,6]. Difficult biliary cannulation is associated with an increased risk of ERCP-related adverse events, such as post-ERCP pancreatitis, bleeding and perforation[7].

Since the first report in 2001[8], an increasing number of studies about the use of endoscopic ultrasound (EUS)-biliary drainage (BD) have been described well enough to suggest this technique as an effective and safe alternative therapy to percutaneous transhepatic BD and surgery in ERCP failure[9-11]. In the current meta-analysis by Peng et al[12] 14 studies involving 620 patients with biliary obstruction treated with EUS-BD after ERCP failure were included. The pooled rates of technical success, clinical success, and reintervention were respectively 96.7%, 91.0%, and 7.3%[12]. An acceptable rate of adverse events is reported (17.5%) with bleeding, cholangitis, and stent occlusion as the most common intra-procedural, post-procedural, and late adverse events, respectively. This study confirmed that EUS-BD is an effective and safe approach when ERCP is impossible, especially using the lumen-apposing metal stents (LAMSs) with electrocautery-enhanced (ECE) technology that, since 2013, have simplified the BD procedure and allowed one-step stent deployment[13]. To manage obstructive jaundice with EUS, the biliary system can be drained by several different routes: The transduodenal (EUS-guided choledochoduodenostomy), transgastric (EUS-guided-hepatogastrostomy) and, more recently, via gallbladder (EUS-guided gallbladder drainage), thus giving several different solutions with respect to the “one-way” ERCP[13,14]. More recently, EUS-BD has even been proposed as the first-line approach for MBO and three randomized trials have demonstrated similar rates of technical and clinical outcomes, comparable to ERCP[15-17]. Furthermore, no significant differences in the overall rate of procedure-related adverse events were reported and post-procedure pancreatitis was significantly higher for ERCP. Such results have raised the question about which technique is better as the primary technique for establishing drainage in MBO[18].

As of today, ERCP remains the first-line therapeutic technique in case of MBO, but interventional EUS is an ever-evolving field with increasing interest by manufacturers in creating dedicated devices and by clinicians to explore new horizons[19,20]. Even gastrointestinal societies are showing a growing interest in defining and increasing the competencies of future endoscopists both in interventional EUS as well as in ERCP by specific training programs with experienced mentors and hands-on sessions[21,22]. As a result, the same endoscopist, with both ERCP and interventional EUS skills, could manage the patient with biliary obstruction throughout the course of the disease, from the diagnosis to different therapeutic scenarios.

CONCLUSION

For about 40 years, therapeutic ERCP and diagnostic EUS have been two clearly distinct techniques, both of them used for the management of biliopancreatic disease but often performed by different operators. The advent of therapeutic EUS has contributed in just a few years to a greater connection of these two techniques thus leading to a change of this paradigm. The introduction of dedicated devices for interventional EUS, such as ECE-LAMs, has opened the gate to the new concept of a “complete biliopancreatic endoscopist”, potentially able to manage complex cases of biliary and pancreatic disease with several different available methods. The development of novel specific devices and dedicated instruments for interventional EUS will overcome the limits for a widespread diffusion of this technique.

The role of EUS, ECE-LAMS, in the management of lower end malignant obstructive jaundice is a paramount relevant to the present. In fact, this is important as a safe, and effective tool. Endoscopists must have the additional EUS skills available on top of ERCP skills, especially in cases of failure to cannulate the lower end bile duct by ERCP. Therefore, EUS and ECE-LAMS can be used for BD in malignant obstruction.