The prognosis of patients with advanced unresectable EHCC is very poor with a median survival of 3 to 6 months. Active control of tumor growth is the key to extending stent patency and survival for patients with unresectable locally advanced EHCC. Photodynamic therapy (PDT) is by far the only modality that has shown to improve stent patency as well as over survival (OS) in patients with cholangiocarcinoma. In recent years, many studies have shown that endoscopic radiofrequency ablation (RFA) extends stent patency and possibly the survival of patients with malignant biliary obstruction. However, there are few reports comparing the clinical efficacy and advers event of these two endoscopic treatment.

Extrahepatic cholangiocarcinoma (EHCC) originates from the hepatic hilar region to the lower common bile duct. The prognosis of patients with advanced unresectable EHCC is very poor with a median survival of 3 to 6 months. Active control of tumor growth is the key to extending stent patency and survival for patients with unresectable locally advanced EHCC. Photodynamic therapy (PDT) is by far the only modality that has shown to improve stent patency as well as over survival (OS) in patients with cholangiocarcinoma. In an attempt to improve stent patency placed for malignant biliary obstruction, enthusiasm for endoscopic retrograde cholangio-pancreatography (ERCP)-guided radiofrequency ablation (RFA) has been increasing in recent years. The HABIBTM EndoHBP catheter is an endoscopic bipolar RFA catheter with proven safety and effectiveness for biliary RFA of cholangiocarcinoma. Many studies have shown that endoscopic RFA extends stent patency and possibly the survival of patients with malignant biliary obstruction. However, there are few reports comparing the clinical efficacy and advers event of these two endoscopic treatment.

Inclusion Criteria:

• histologically or cytologically confirmed cholangiocarcinoma;
• unresectable cholangiocarcinoma due to local infiltration of major vessels according to computed tomography (CT), magnetic resonance cholangiopancreatography (MRCP), or endoscopic ultrasound（EUS）;
• no previous treatment;
• adequate bone marrow and organ function (white blood cells>4.0×109/L, hemoglobin>90 g/L, and platelets>75×109/L, serum creatinine<2.0 mg/dl);
• a Karnofsky performance status (KPS) score ≥ 50;
• signed written informed consent.

Exclusion Criteria:

• imaging examination (CT, MRCP, EUS) showed distant metastasis of liver, lung and other organs;
• coexistent with other malignant tumors;
• pregnant or nursing women;
• previous gastrointestinal diversion;
• participation in another study during the month before enrollment in this study;
• alcohol and/or substance abuse or potentially poor compliance per a doctor's judgment.