title: A comparison of uncovered metal stents for the palliation of patients with malignant biliary obstruction: nitinol vs. stainless steel.
abstract: BACKGROUND
  Various types of self-expandable metal stents have been introduced for the palliation of malignant biliary obstruction.
  
  
  OBJECTIVE
  To compare the outcomes of WallFlex™ and Wallstent™ uncovered biliary self-expandable metal stents (SEMSs) for the palliation of patients with malignant biliary obstruction.
  
  
  METHODS
  Between October 2008 and December 2009, all SEMSs placed for malignant biliary obstruction were WallFlex™: all patients palliated were included in the study. Before October 2008, all the SEMSs placed for malignant biliary obstruction were Wallstent™, and the patients palliated from July 2007 to September 2008 were the comparative group.
  
  
  RESULTS
  A total of 58 WallFlex™ and 54 Wallstent™ SEMSs were placed, and efficacious biliary decompression was achieved in all patients. Early complications occurred in 5 patients in the WallFlex™ group and in 3 in the Wallstent™ group (p=ns). Late complications occurred in 6 patients in the WallFlex™ group and in 16 in the Wallstent™ group (p<0.01). The overall patency of the self-expandable metal stent in the WallFlex™ and the Wallstent™ groups was similar (227 days vs. 215 days, p=ns). Mean patient survival was 242 days in the WallFlex™ group and 257 days in the Wallstent™ group (p=ns).
  
  
  CONCLUSIONS
  We found no difference in terms of overall patency between the two types of SEMSs, but there was an increased rate of late adverse events in the Wallstent™ group.
authors.affiliation: Unit of Gastroenterology and Digestive Endoscopy, AUSL Bologna Bellaria-Maggiore Hospital, Bologna, Italy. carmeluigiano@libero.it
authors.forename: Carmelo
authors.initials: C
authors.lastname: Luigiano
authors.forename: Francesco
authors.initials: F
authors.lastname: Ferrara
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Cennamo
authors.forename: Carlo
authors.initials: C
authors.lastname: Fabbri
authors.forename: Marco
authors.initials: M
authors.lastname: Bassi
authors.forename: Stefania
authors.initials: S
authors.lastname: Ghersi
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Consolo
authors.forename: Carmela
authors.initials: C
authors.lastname: Morace
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Polifemo
authors.forename: Paola
authors.initials: P
authors.lastname: Billi
authors.forename: Liza
authors.initials: L
authors.lastname: Ceroni
authors.forename: Angela
authors.initials: A
authors.lastname: Alibrandi
authors.forename: Nicola
authors.initials: N
authors.lastname: D'Imperio
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000497:Alloys; D044963:Biopsy, Fine-Needle; D002760:Cholangiopancreatography, Endoscopic Retrograde; D002779:Cholestasis / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D019160:Endosonography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010166:Palliative Care / Q000379:methods*; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000175:diagnosis; D011474:Prosthesis Design; D012189:Retrospective Studies; D013193:Stainless Steel; D015607:Stents; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D000497:Alloys; D013193:Stainless Steel; C013616:nitinol