Brief Article
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World J Gastroenterol. Dec 14, 2013; 19(46): 8638-8646
Published online Dec 14, 2013. doi: 10.3748/wjg.v19.i46.8638
Randomized trial in malignant biliary obstruction: Plastic vs partially covered metal stents
Peter L Moses, Khalid M AlNaamani, Alan N Barkun, Stuart R Gordon, Roger D Mitty, M Stanley Branch, Thomas E Kowalski, Myriam Martel, Viviane Adam
Peter L Moses, Division of Gastroenterology and Hepatology, University of Vermont, Burlington, VT 05401, United States
Khalid M AlNaamani, Alan N Barkun, Myriam Martel, Viviane Adam, Division of Gastroenterology, McGill University Health Center, McGill University, Montréal, Québec H3G 1A4, Canada
Alan N Barkun, Department of Epidemiology and Biostatistics and Occupational Health, McGill University Health Center, McGill University, Montréal, Québec H3G 1A4, Canada
Stuart R Gordon, Division of Gastroenterology and Hepatology, Dartmouth Hitchcock Medical Center, Lebanon, NH 03766, United States
Roger D Mitty, Division of Gastroenterology, Tufts University School of Medicine, Boston, MA 02111, United States
M Stanley Branch, Division of Gastroenterology, Duke University Medical Center, Durham, NC 27710, United States
Thomas E Kowalski, Division of Gastroenterology and Hepatology, Thomas Jefferson University Hospital, Philadelphia, PA 19107, United States
Author contributions: Moses PL, Barkun AN, Gordon SR, Mitty RD, Branch MS, Kowalski TE designed research; Moses PL, AlNaamani KM, Barkun AN, Gordon SR, Mitty RD, Branch MS, Kowalski TE performed research; Moses PL, AlNaamani KM, Barkun AN, Gordon SR, Mitty RD, Branch MS, Kowalski TE, contributed new reagents or analytic tools; Moses PL, Barkun AN, Martel M, Adam V analyzed data; Moses PL, Barkun AN, Martel M, Adam V wrote the paper.
Supported by Research Funding from Boston Scientific Inc to Barkun AN; Research Funding from Cook Endoscopy to Branch MS; Research Funding from Pentax Corp to Kowalski TE
Correspondence to: Alan N Barkun, MD, CM, FRCP(C), FACP, FAGA, FACG, MSc, Chairholder, Professor, Division of Gastroenterology, McGill University Health Center, McGill University, Montreal General Hospital site, 1650 Cedar Avenue, room D16.125, Montréal H3G 1A4, Canada. alan.barkun@muhc.mcgill.ca
Telephone: +1-514-9348309 Fax: +1-514-8348531
Received: March 19, 2013
Revised: July 17, 2013
Accepted: September 4, 2013
Published online: December 14, 2013
Processing time: 273 Days and 13.1 Hours
Abstract

AIM: 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.

CONCLUSION: 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.

Keywords: Randomized; Biliary; Obstruction; Stent; Plastic; Metal; Palliative; Common bile duct

Core tip: This randomized trial is one of very few comparing partially covered self-expandable metal stent (SEMS) to 10 French plastic stent (PS) in the contemporary palliation of malignant biliary obstruction. In 85 patients, time to stent failure was significantly longer (385.3 ± 52.5 d) in SEMS vs PS (153.3 ± 19.8 d), P = 0.006. Time to death did not differ (192.3 ± 23.4 d for SEMS vs 211.5 ± 28.0 d for PS, P = 0.70). Amongst other measured outcomes, only cholangitis differed and was more common in PS (4.9% vs 24.5%, P = 0.029).