title: Covered versus uncovered self-expandable metallic stents for palliation of malignant pyloric obstruction in gastric cancer patients: a randomized, prospective study.
abstract: BACKGROUND
  Self-expandable metallic stents (SEMSs) provide effective palliation of malignant pyloric obstruction in patients with inoperable gastric cancer.
  
  
  OBJECTIVE
  To compare the effectiveness and side effects of covered and uncovered SEMSs for the palliation of malignant pyloric obstruction.
  
  
  METHODS
  Prospective, randomized, single-center study.
  
  
  METHODS
  Tertiary-care cancer center hospital.
  
  
  METHODS
  This study involved 80 patients with pyloric obstruction related to inoperable gastric cancer.
  
  
  METHODS
  Covered or uncovered SEMS placement.
  
  
  METHODS
  Technical and clinical success rates as well as the patency rate at 8 weeks after placement.
  
  
  RESULTS
  Both groups had a technical success rate of 100% with no immediate complications. Both groups also had comparable clinical success rates (covered SEMS, 95% [38 of 40] and uncovered SEMS, 90% [36 of 40], P = .68) and 8-week patency rates (covered SEMS, 61.3% [19 of 31] and uncovered SEMS, 61.1% [22 of 36], P > .99). Stent migration within 8 weeks was more common in the covered SEMS group (25.8% [8 of 31]) than in the uncovered SEMS group (2.8% [1 of 36], P = .009), whereas re-stenosis because of tumor ingrowth was more common in the uncovered SEMS group (25.0% [9 of 36] vs 0% [0 of 31] in the covered SEMS group, P = .003). Overall patient survival and stent patency did not differ between groups (P = .27 and 0.61 by log-rank test, respectively).
  
  
  CONCLUSIONS
  The study population was limited to gastric cancer patients, and stent designs were changed in the midst of the study period.
  
  
  CONCLUSIONS
  Both the covered and uncovered SEMSs are effective and have comparable 8-week patency in patients with malignant pyloric obstruction, despite different patterns of late stent failure.
authors.affiliation: Center for Gastric Cancer, National Cancer Center, Goyang, Korea.
authors.forename: Chan Gyoo
authors.initials: CG
authors.lastname: Kim
authors.forename: Il Ju
authors.initials: IJ
authors.lastname: Choi
authors.forename: Jong Yeul
authors.initials: JY
authors.lastname: Lee
authors.forename: Soo-Jeong
authors.initials: SJ
authors.lastname: Cho
authors.forename: Sook Ryun
authors.initials: SR
authors.lastname: Park
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Keun Won
authors.initials: KW
authors.lastname: Ryu
authors.forename: Young-Woo
authors.initials: YW
authors.lastname: Kim
authors.forename: Young Iee
authors.initials: YI
authors.lastname: Park
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002173:Cancer Care Facilities; D020099:Coated Materials, Biocompatible; D004867:Equipment Design; D004868:Equipment Failure; D005260:Female; D005548:Foreign-Body Migration / Q000209:etiology; D005773:Gastroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010166:Palliative Care; D011446:Prospective Studies; D011707:Pyloric Stenosis / Q000628:therapy*; D012008:Recurrence; D015607:Stents; D013274:Stomach Neoplasms / Q000473:pathology / Q000628:therapy*
chemical_list: D020099:Coated Materials, Biocompatible