Which approach should be used for endoscopic ultrasound-guided biliary drainage?

We read with great interest the study by Ogura et al. [1] that retrospectively compared the clinical outcome of endoscopic ultrasound (EUS)-guided choledochoduodenostomy (EUS-CD) versus hepaticogastrostomy (EUS-HG) for distal bile duct drainage in 39 patients with concomitant duodenal obstruction. Overall, they found that EUS-HG was associated with significantly longer stent patency and fewer adverse events than EUS-CD. Therefore, the authors concluded that EUS-HG should be preferred over EUS-CD.

This finding is in contrast with the results of a recently published international multicenter, retrospective study involving 121 patients (73 of them with gastric/duodenal outlet obstruction) [2]. In this latter study, the authors found that there was no difference between EUS-HG and EUS-CD in terms of both the technical and clinical success rates [2]. However, the rates of stent occlusion and migration were twice as high in patients who underwent EUS-HG when compared to patients undergoing EUS-CD. In addition, a trend toward an increased risk of adverse events was also observed in the EUS-HG group. 

These conflicting results deserve some explanations. In the study by Ogura and co-workers [1], two different types of stent were used, thereby introducing a potential bias. Indeed, the EUS-HG was performed with a dedicated self-expanding metal stent (SEMS; End-bare type, Niti-S biliary covered stent; TaeWoong Medical, Seoul, South Korea) that was specifically designed for this type of procedure, while for EUS-CD a “tubular” SEMS usually used for transpapillary biliary drainage was used. In the study by Khashab et al. [2], standard non-dedicated stents were used for both procedures. Therefore, the conclusion drawn by Ogura et al. may be due to the different type of devices used, rather than to the route of drainage chosen.

Newly designed lumen-apposing SEMSs (Hot Axios; Boston Scientific Corp., Marlborough, Massachusetts, USA) are now available specifically to perform EUS-CD. A recently published multicenter retrospective study, which included 57 patients (41 of them with duodenal stenosis), showed that the Axios stent achieved very high technical (98.2 %) and clinical (94.7 %) success rates for EUS-CD [3]. In addition, in patients with concomitant duodenal stenosis, these stents allow duodenal stenting to be performed the same day without any interference [3]. Conversely, duodenal stenting should always precede EUS-CD with “tubular” stents in order to create enough space to allow the placement of a 6-cm biliary stent. Moreover, the hot-Axios is also incorporated into an electrocautery-enhanced delivery system that permits direct puncture, penetration of the bile duct, and release of the stent in a one-step procedure without the need to exchange accessories, mostly under complete EUS guidance [4].

In our opinion, prospective studies comparing stents specifically designed for biliary drainage, such as the End-bare type and the Hot-Axios, should be designed in order to clearly understand all the potentialities of this procedure. We strongly believe that this is just the beginning of a new era where EUS-guided biliary drainage can, not only, take over and completely replace percutaneous drainage, but can also become a real alternative to endoscopic retrograde cholangiopancreatography (ERCP) for primary palliation of patients with unresectable malignant biliary obstruction [5].

• References

• 1 Ogura T, Chiba Y, Masuda D et al. Comparison of the clinical impact of endoscopic ultrasound-guided choledochoduodenostomy and hepaticogastrostomy for bile duct obstruction with duodenal obstruction. Endoscopy 2016; 48: 156-163
• 2 Khashab MA, Messallam AA, Penas I et al. International multicenter comparative trial of transluminal EUS-guided biliary drainage via hepatogastrostomy vs. choledochoduodenostomy approaches. Endosc Int Open 2016; 4: E175-E181
• 3 Kunda R, Pérez-Miranda M, Will U et al. EUS-guided choledochoduodenostomy for malignant distal biliary obstruction using a lumen-apposing fully covered metal stent after failed ERCP. Surg Endosc . Epub ahead of print 11 March 2016
• 4 Attili F, Rimbaș M, Galasso D et al. Fluoroless endoscopic ultrasound-guided biliary drainage after failed ERCP with a novel lumen-apposing metal stent mounted on a cautery-tipped delivery system. Endoscopy 2015; 47: E619-E620
• 5 Moon JH, Choi HJ, Lee YN. Will endoscopic ultrasound-guided bile duct drainage replace ERCP?. Endoscopy 2016; 48: 107-109