The study was terminated because of difficulty in completing the study as originally planned

Biliary drainage is the mainstay of the palliative treatment in patients with inoperable malignant bile duct stricture. Endoscopic retrograde cholangiopancreatography (ERCP) is the cornerstone of biliary drainage method in these patients. However, ERCP is sometime unsuccessful to perform because of the presence of the high grade biliary stricture, tumor invasion of duodenum and ampulla of vater and surgically altered gastrointestinal anatomy. Endoscopic ultrasound (EUS) guided biliary drainage has been emerged as an alternative procedure to traditional surgical bypass and percutaneous trans hepatic biliary drainage after failed ERCP. There were few data to directly compare between ERCP and EUS guided biliary drainage and in patients with malignant high grade biliary stricture.

The aim of this study is comparing the efficacy and complications between ERCP and EUS guided biliary drainage in patients with malignant high grade biliary stricture. Malignant high grade biliary stricture has not been well defined. The investigators define this malignant high grade biliary stricture using these arbitrary number include total bilirubin ≥ 15 mg/dl and or bile duct diameter ≥12 mm. based on the investigation's experience.

The study will be divided patients with inoperable malignant high grade biliary stricture into 2 groups, group (A) will be undergone ERCP with biliary stenting and group (B) will be undergone EUS guided biliary drainage. If the assigned intervention is not successful, then patients will be crossed-over to the another intervention.

Inclusion Criteria: I) Patients aged > 18 years. II) Clinical, laboratory data, imaging and or histology suggestive of malignant distal bile duct strictures that occurs as a result of pancreatic adenocarcinoma, cholangiocarcinoma, ampullary carcinoma, duodenal carcinoma, gallbladder cancer and metastasis malignant bile duct obstruction III) Inoperability by tumor staging, medically unfit or patient wishes

1. distant metastasis
2. major vascular involvement (unreconstructible Superior mesenteric vein/Portal vein, superior mesenteric artery, common hepatic artery and celiac artery)
3. metastasis to lymphnode beyond the field or surgery IV) Jaundice, total bilirubin ≥15 mg/dl and/ or Common bile duct diameter ≥12 mm

Exclusion Criteria: I) pregnancy II) uncorrectable coagulopathy ( international normalized ratio ≥ 1.5 ) III) thrombocytopenia (platelet count < 50,000 ) IV) extremely poor general condition, ERCP with stent insertion impossible for ethical reasons V) an extension of stricture to the main biliary confluent (hilum) or the existence of obstructive duodenal invasion VI) active suppurative cholangitis VI) surgically altered anatomy (i.e. Billroth II or Roux-en-Y reconstruction ) VII ) previous treatment with bile duct stent.

The individual data of patients participating in the study are not available for public sharing since the investigators did not obtain the consent to share the data of patient.