title: Randomized trial in malignant biliary obstruction: plastic vs partially covered metal stents.
abstract: OBJECTIVE
  To compare efficacy and complications of partially covered self-expandable metal stent (pcSEMS) to plastic stent (PS) in patients treated for malignant, infrahilar biliary obstruction.
  
  
  METHODS
  Multicenter prospective randomized clinical trial with treatment allocation to a pcWallstent(®) (SEMS) or a 10 French PS. Palliative patients aged ≥ 18, for infrahilar malignant biliary obstruction and a Karnofsky performance scale index > 60% from 6 participating North American university centers. Primary endpoint was time to stent failure, with secondary outcomes of death, adverse events, Karnofsky performance score and short-form-36 scale administered on a three-monthly basis for up to 2 years. Survival analyses were performed for stent failure and death, with Cox proportional hazards regression models to determine significant predictive characteristics.
  
  
  RESULTS
  Eighty-five patients were accrued over 37 mo, 42 were randomized to the SEMS group and 83 patients were available for analyses. Time to stent failure was 385.3 ± 52.5 d in the SEMS and 153.3 ± 19.8 d in the PS group, P = 0.006. Time to death did not differ between groups (192.3 ± 23.4 d for SEMS vs 211.5 ± 28.0 d for PS, P = 0.70). The only significant predictor was treatment allocation, relating to the time to stent failure (P = 0.01). Amongst other measured outcomes, only cholangitis differed, being more common in the PS group (4.9% vs 24.5%, P = 0.029). The small number of patients in follow-up limits longitudinal assessments of performance and quality of life. From an initially planned 120 patients, only 85 patients were recruited.
  
  
  CONCLUSIONS
  Partially covered SEMS result in a longer duration till stent failure without increased complication rates, yet without accompanying measurable benefits in survival, performance, or quality of life.
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Peter L
authors.initials: PL
authors.lastname: Moses
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Khalid M
authors.initials: KM
authors.lastname: Alnaamani
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Alan N
authors.initials: AN
authors.lastname: Barkun
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Stuart R
authors.initials: SR
authors.lastname: Gordon
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Roger D
authors.initials: RD
authors.lastname: Mitty
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: M Stanley
authors.initials: MS
authors.lastname: Branch
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Kowalski
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Myriam
authors.initials: M
authors.lastname: Martel
authors.affiliation: Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States.
authors.forename: Viviane
authors.initials: V
authors.lastname: Adam
mesh_terms: D000046:Academic Medical Centers; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D002779:Cholestasis / Q000175:diagnosis / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D004322:Drainage / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D017567:Karnofsky Performance Status; D008297:Male; D008670:Metals; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications* / Q000401:mortality; D009656:North America; D010166:Palliative Care; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011474:Prosthesis Design; D011788:Quality of Life; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D008670:Metals
keywords: Biliary; Common bile duct; Metal; Obstruction; Palliative; Plastic; Randomized; Stent