title: Comparison of the utility of covered metal stents versus uncovered metal stents in the management of malignant biliary strictures in 749 patients.
abstract: BACKGROUND
  Self-expandable metal stents (SEMSs) are used to relieve malignant biliary obstruction.
  
  
  OBJECTIVE
  To compare outcomes between covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (USEMSs) in malignant biliary obstruction.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Tertiary cancer center.
  
  
  METHODS
  Patients with malignant biliary obstruction.
  
  
  METHODS
  Placement of CSEMS or USEMS.
  
  
  METHODS
  Time to recurrent biliary obstruction (TRO), overall survival (OS), and adverse events.
  
  
  RESULTS
  From January 2000 to June 2011, 749 patients received SEMSs: 171 CSEMSs and 578 USEMSs. At 1 year, there was no significant difference in the percentage of patients with recurrent obstruction (CSEMSs, 35% vs USEMSs, 38%) and survival (CSEMSs, 45% vs USEMSs, 49%). There was no significant difference in the median OS (CSEMSs, 10.4 months vs USEMSs, 11.8 months; P = .84) and the median TRO (CSEMSs, 15.4 months vs USEMSs, 26.3 months; P = .61). The adverse event rate was 27.5% for the CSEMS group and 27.7% for the USEMS group. Although tumor ingrowth with recurrent obstruction was more common in the USEMS group (76% vs 9%, P < .001), stent migration (36% vs 2%, P < .001) and acute pancreatitis (6% vs 1%, P < .001) were more common in the CSEMS group.
  
  
  CONCLUSIONS
  Retrospective study.
  
  
  CONCLUSIONS
  There was no significant difference in the patency rate or overall survival between CSEMSs and USEMSs for malignant distal biliary strictures. The CSEMS group had a significantly higher rate of migration and pancreatitis than the USEMS group. No significant SEMS-related adverse events were observed in patients undergoing neoadjuvant chemoradiation or surgical resection.
authors.affiliation: Department of Gastroenterology, Hepatology, and Nutrition, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA. jefflee@mdanderson.org
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Lee
authors.forename: Somashekar G
authors.initials: SG
authors.lastname: Krishna
authors.forename: Amanpal
authors.initials: A
authors.lastname: Singh
authors.forename: Harshad S
authors.initials: HS
authors.lastname: Ladha
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Slack
authors.forename: Srinivas
authors.initials: S
authors.lastname: Ramireddy
authors.forename: Gottumukkala S
authors.initials: GS
authors.lastname: Raju
authors.forename: Marta
authors.initials: M
authors.lastname: Davila
authors.forename: William A
authors.initials: WA
authors.lastname: Ross
mesh_terms: D000368:Aged; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000295:instrumentation*; D002779:Cholestasis / Q000209:etiology / Q000628:therapy*; D015331:Cohort Studies; D018572:Disease-Free Survival; D004867:Equipment Design; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000150:complications*; D012008:Recurrence; D012189:Retrospective Studies; D015607:Stents; D016896:Treatment Outcome
chemical_list: D008670:Metals
keywords: CSEMS; OS; ROFS; SE; SEMS; TRO; USEMS; covered self-expandable metal stent; overall survival; recurrent obstruction–free survival; self-expandable metal stent; standard error; time to recurrent biliary obstruction; uncovered self-expandable metal stent