Unilateral Versus Bilateral Stents for Bismuth Type II and III Malignant Hilar Strictures

Inclusion Criteria: * Consecutive untreated patients with biliary obstruction (Bismuth type II, III) at the hilum due to primary cholangiocarcinoma, gallbladder cancer, or periportal lymph node metastases. Diagnosis is based on US, CT, and MRCP. * Histologic or cytologic confirmation of malignancy is established by percutaneous biopsy (US- or CT-guided) or by endoscopic tissue sampling, endoscopic brushing. Or the diagnosis is based on typical features on imaging and the expected clinical outcome during follow-up. * All patients were considered unsuitable for resection on the basis of general medical condition and/or tumor extent. * Full and informed consent is obtained. Exclusion Criteria: * Refuse to participate in this study. * Refuse to provide informed consent. * Refuse to be placed with plastic stents. * Physically unfit for endoscopic treatment.