The aim of the present study was to compare the effect of unilateral versus bilateral stenting in patients with malignant hilar obstruction.

Cholangiocarcinoma accounts for 3% of all gastrointestinal cancers and is the second commonest primary liver cancer. However only a few patients are suitable for surgical resection and therefore endoscopic biliary drainage is the most used palliative treatment modality for malignant hilar stricture. However, whether one or two stents can benefit the patients most is still to be defined. Numerous retrospective case series reached different conclusion, till now, only one randomized trial compared the effect of unilateral versus bilateral stenting in patients with malignant hilar obstruction, nonetheless, nearly one third of the patients had Bismuth Type I stricture, and one stent is enough for drainage in this situation, therefore, the best drainage strategy for patients with Bismuth Type II or Bismuth Type III malignant hilar obstruction is unknown. The aim of the present study was to compare the effect of unilateral versus bilateral stenting in patients with Bismuth Type II or III malignant hilar obstruction.

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.