The purpose of this study is to compare the clinical effectiveness and long-term outcomes between patients with pancreatic carcinoma and biliary obstruction who are treated by stent insertion with or without high-intensity focused ultrasound ablation.

Distal malignant biliary obstruction is a common problem in patients with pancreatic carcinoma. In unresectable pancreatic carcinomas, percutaneous stent placement has been pivotal in providing relief from obstructive jaundice, improving the quality of life, and allowing the maintenance of anticancer treatment.

Venous chemotherapy, transcatheter arterial chemoembolization, or radiotherapy have been used to prolong stent patency and survival after stent insertion for patients with pancreatic carcinoma and biliary obstruction. High-intensity focused ultrasound ablation is a noninvasive and atoxic treatment of malignant tumor using focused ultrasound energy from an extracorporeal source that is targeted within the body resulting in thermally induced necrosis and apoptosis.

The purpose of this study is to compare the clinical effectiveness and long-term outcomes between patients with pancreatic carcinoma and biliary obstruction who are treated by stent insertion with or without high-intensity focused ultrasound ablation.

Inclusion Criteria:

1. malignant distal biliary obstruction;
2. pathologically diagnosed pancreatic carcinoma;
3. unresectable cases.

Exclusion Criteria:

1. inability to obtain informed consent;
2. Eastern Cooperative Oncology Group performance status of 4;
3. life expectancy of 3 months or less;
4. biliary obstruction that was not directly caused by pancreatic carcinoma.

There is not a plan to make individual participant data available.