Although endoscopic retrograde cholangiopancreatography (ERCP) is almost always successful in patients with malignant biliary obstruction, selective biliary cannulation fails in some cases and conventional ERCP may not be possible in patients with tumor invasion of the duodenum or major papilla, surgically altered anatomy (e.g., Roux-en-Y anastomosis), or complex hilar biliary strictures. In such cases, percutaneous transhepatic biliary drainage (PTBD) is an useful alternative. However, PTBD had various complications and the presence of an external drainage catheter would also have a cosmetic problem related to the external drainage and an adverse impact on quality of life (QOL) of terminally ill patients.

Since endoscopic ultrasound-guided bile duct puncture was described in 1996, sporadic case reports of EUS-guided biliary drainage (EUS-BD) suggested that it was a feasible and effective alternative in patients with failed conventional ERCP stenting. The potential benefits of EUS-BD include one-stage procedure in ERCP unit, and internal drainage for avoiding long-term external drainage in cases where external PTBD drainage catheters cannot be internalized, thus significantly improving the QOL of terminally ill patients, and possibly lower morbidity than PTBD or surgery.

Up to date, only a few case series of EUS-BD with small numbers of patients have been published, and known the feasibility and safety in terms of the incidence of procedure-related clinical outcomes.

We investigated the efficacy and safety of EUS-BD using partially covered (hybrid) metallic stent with a dedicated introducer for EUS-BD, or fully covered antimigration metallic stents in malignant biliary obstruction after failed conventional ERCP as a prospective multicenter study.

Inclusion Criteria:

• malignant biliary obstruction
• Inoperable state
• age > 18 yrs
• failed primary ERCP

Exclusion Criteria:

• uncontrolled coagulopathy
• refuse to this study enrollment