Although 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.10-21 There has been no comparative study between the outcomes of PTBD and EUS-BD focusing on the QOL, cost-effectiveness, and complications.

The researchers investigated the technical success of EUS-BD and PTBD in patients with malignant biliary obstruction after failed conventional ERCP as a prospective randomized comparative study in multicenters. Secondary endpoints were the cost-effectiveness and complications rates between EUS-BD and PTBD.

Inclusion Criteria:

• Presence of unresectable malignant distal biliary obstruction (greater 2cm than distal to hilum, i.e., pancreatic cancer, common bile duct cancer, ampulla of Vater cancer, gallbladder cancer, duodenal cancer, and metastatic biliary obstruction)
• Failed conventional ERCP and inaccessible papilla because of accompanying duodenal obstruction, periampullary tumor infiltration, ampulla stenosis, or surgically altered anatomy (Billroth II operation, Roux-an-Y operation.)
• Histologic or cytologic diagnosis of malignancy, d) A Karnofsky index of ≧30%, e) No serious or uncontrolled medical illness
• Provided informed consent.

Exclusion Criteria:

• patient age of less than 18 years
• uncorrectable coagulopathy
• history of allergy to radiocontrast agents
• refusal to participate in this study.