title: Conformable covered versus uncovered self-expandable metallic stents for palliation of malignant gastroduodenal obstruction: a randomized prospective study.
abstract: BACKGROUND
  A conformable self-expandable metallic stent was developed to overcome the limitation of previous self-expandable metallic stents. The aim of this study was to evaluate outcomes after placement of conformable covered and uncovered self-expandable metallic stents for palliation of malignant gastroduodenal obstruction.
  
  
  METHODS
  A single-blind, randomized, parallel-group, prospective study were conducted in 4 medical centres between March 2009 and July 2012. 134 patients with unresectable malignant gastroduodenal obstruction were assigned to a covered double-layered (n=66) or uncovered unfixed-cell braided (n=68) stent placement group. Primary analysis was performed to compare re-intervention rates between two groups.
  
  
  RESULTS
  120 patients were analysed (59 in the covered group and 61 in the uncovered group). Overall rates of re-intervention were not significantly different between the two groups: 13/59 (22.0%) in the covered group vs. 13/61 (21.3%) in the uncovered group, p=0.999. Stent migration was more frequent in the covered group than in the uncovered group (p=0.003). The tumour ingrowth rate was higher in the uncovered group than in the covered group (p=0.016).
  
  
  CONCLUSIONS
  The rates of re-intervention did not significantly differ between the two stents. Conformable covered double-layered and uncovered unfixed-cell braided stents were associated with different patterns of stent malfunction.
authors.affiliation: Department of Gastroenterology, Ajou University School of Medicine, Suwon, Republic of Korea.
authors.forename: Sun Gyo
authors.initials: SG
authors.lastname: Lim
authors.affiliation: Department of Gastroenterology, Ajou University School of Medicine, Suwon, Republic of Korea. Electronic address: jinhkim@ajou.ac.kr.
authors.forename: Jin Hong
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Gastroenterology, Ajou University School of Medicine, Suwon, Republic of Korea.
authors.forename: Kee Myung
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, Ajou University School of Medicine, Suwon, Republic of Korea.
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Shin
authors.affiliation: Department of Gastroenterology, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Chan Gyoo
authors.initials: CG
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Hallym University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kyung Ho
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea.
authors.forename: Ho Gak
authors.initials: HG
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Dongguk University College of Medicine, Gyeongju, Republic of Korea.
authors.forename: Chang Heon
authors.initials: CH
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000497:Alloys; D004067:Digestive System Neoplasms / Q000150:complications*; D004380:Duodenal Obstruction / Q000209:etiology / Q000628:therapy*; D005260:Female; D017219:Gastric Outlet Obstruction / Q000209:etiology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010166:Palliative Care; D011446:Prospective Studies; D011475:Prosthesis Failure / Q000209:etiology*; D019233:Retreatment; D016037:Single-Blind Method; D015607:Stents / Q000009:adverse effects
chemical_list: D000497:Alloys; C013616:nitinol
keywords: Gastroduodenal obstruction; Palliative treatment; Stent