title: Stent collapse as a delayed complication of placement of a covered gastroduodenal stent.
abstract: OBJECTIVE
  The purpose of this study was retrospective evaluation of the incidence, predictive factors, and interventional management of stent collapse after placement of a covered metallic stent in patients with obstruction of the gastric outlet or duodenum due to malignant disease.
  
  
  METHODS
  Among 259 patients with symptomatic malignant gastroduodenal obstruction successfully treated with stent placement, stent collapse occurred in 12 (4.6%) of the patients 34-270 days (mean, 101.8 days) after stent placement. Multivariate analysis was performed to evaluate factors predictive of stent collapse. Interventional management of stent collapse also was evaluated.
  
  
  RESULTS
  Multivariate analysis showed that presence of the stent in the peripyloric region (odds ratio, 27.745; p = 0.036), longer survival time (odds ratio, 1.016; p < 0.001), and absence of chemotherapy after stent placement (odds ratio, 31.661; p = 0.048) were independent predictors of stent collapse. Eleven patients with stent collapse were successfully treated with placement of a second bare stent. The twelfth patient refused further treatment.
  
  
  CONCLUSIONS
  Stent collapse is an uncommon delayed complication of placement of covered metallic stents in patients with malignant gastroduodenal obstruction. Collapse occurs most commonly in the peripyloric region, in patients with longer survival times, and in patients who do not undergo chemotherapy after stent placement. Stent collapse can be managed by coaxial placement of a second bare stent into the collapsed stent.
authors.affiliation: Department of Radiology, Asan Medical Center, 388-1 Pungnap-2dong, Songpa-gu, Seoul, Seoul, South Korea 138-736.
authors.forename: Jin Hyoung
authors.initials: JH
authors.lastname: Kim
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Song
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Shin
authors.forename: Eugene
authors.initials: E
authors.lastname: Choi
authors.forename: Tae Won
authors.initials: TW
authors.lastname: Kim
authors.forename: Sung Koo
authors.initials: SK
authors.lastname: Lee
authors.forename: Byung Sik
authors.initials: BS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D015897:Comorbidity; D004379:Duodenal Neoplasms / Q000453:epidemiology / Q000628:therapy; D004380:Duodenal Obstruction / Q000453:epidemiology* / Q000628:therapy*; D005260:Female; D017219:Gastric Outlet Obstruction / Q000453:epidemiology* / Q000628:therapy*; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D015641:Radiography, Interventional / Q000706:statistics & numerical data; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015607:Stents / Q000706:statistics & numerical data*; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000628:therapy; D013997:Time Factors; D016896:Treatment Outcome