The Gore Viabil Biliary Endroprosthesis is used to control cases of biliary malignancy. It uses a ePTFE/FEP liner that will not collect water or other fluids and will create a barrier that keeps tissue ingrowth from developing. The nitinol stent is flexible and has a better radial strength level when used at body temperature, thus making it stronger than most metallic stents. The material can be used in an endoscopic or percutaneous method when inserted.