Self-conformable covered vs self-conformable uncovered metallic stents in the palliative treatment of malignant extra-hepatic biliary stricture: a multicentric randomized study.

Introduction: Cancer of the pancreas, gallbladder and bile ducts is the most common cause of malignant neoplastic obstruction of the biliary tree. In the case of advanced and unresectable cancer, the prognosis is poor, with a survival rate at 5 years less than 2%. We present preliminary results of an prospective controlled trial comparing covered (Niti-S Biliary ComVi) with uncovered (Niti-s D type) self-conformable metal stent for palliation of symptoms (jaundice and/or cholangitis) in patients with primary malignant extra-hepatic biliary obstruction, not eligible for surgery. No RCTs are present in literature comparing the two different types of self-conformable stents. Aims: The primary aim of our study was to compare the duration of stent patency between the two types of stents. Secondary aims were to address relationships between complication rate and stent type, to evaluate time of stent dysfunction-free and difference in survival of patients. Methods: 158 patients (76 male and 82 female, median age 78 years) were randomized to have a covered (78 FCSEM) or an uncovered (80 SEMS) stent. Data from 148 (72 FCSEMS and 76 USEMS) out of 158 patients were analyzed. Inclusion criteria were: age ≥ 18 years; malignant obstruction of the extrahepatic common bile duct (CBD) amenable to stent placement; serum bilirubin levels > 30 micromol/lt; inoperability because of the poor medical conditions and/or to the absence of curative surgical resection due to tumor stage, or patient wishes; capability to provide a written informed consent. Exclusion criteria were: benign biliary obstruction; compression caused by metastatic lymphadenopathy, malignancies involving hepatic hilum or the duodenum; previous gastric bypass