title: How to design the optimal self-expandable oesophageal metallic stents: 22 years of experience in 645 patients with malignant strictures.
abstract: OBJECTIVE
  To evaluate the clinical efficacy and safety of self-expandable metallic stent (SEMS) placement for malignant oesophageal strictures and their relationship with stent designs.
  
  
  METHODS
  Seven generations of SEMS were used to treat 645 consecutive patients with oesophageal strictures. Logistic regression models were constructed to identify predictive factors associated with complications.
  
  
  RESULTS
  Stent placement was technically successful in 641 of 645 patients (99.4%). The clinical success rate was 95.5%. There were 260 (40.3%) complications after stent placement. Due to complications, 68 stents were removed; 66 of 68 stents (97.1%) were removed successfully. Stainless steel (SS) stents (odds ratio [OR] 4.18; 95% confidence interval [CI] 2.10, 8.32) and radiation therapy (RT) before stent placement (OR 4.23; CI 2.02, 8.83) were significantly associated with severe pain. Flared ends (OR 9.63; CI 3.38, 27.43), stricture length <6 cm (OR 2.01; CI 1.13, 3.60), and a stent diameter <18 mm (OR 3.00; CI 1.32, 6.84) were predictive factors of stent migration. Polyurethane membranes were associated with more frequent tumour ingrowth than polytetrafluoroethylene (PTFE) membranes (P = 0.002).
  
  
  CONCLUSIONS
  Despite the relatively high complication rate, retrievable self-expandable PTFE-covered nitinol stents equipped with a head and a tail appeared to be an effective treatment for malignant oesophageal strictures.
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap 2-dong, Songpa-gu, Seoul 138-736, Republic of Korea.
authors.forename: Han Kyu
authors.initials: HK
authors.lastname: Na
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Song
authors.forename: Jin Hyoung
authors.initials: JH
authors.lastname: Kim
authors.forename: Jung-Hoon
authors.initials: JH
authors.lastname: Park
authors.forename: Min Kyoung
authors.initials: MK
authors.lastname: Kang
authors.forename: Jongjin
authors.initials: J
authors.lastname: Lee
authors.forename: Se Jin
authors.initials: SJ
authors.lastname: Oh
mesh_terms: D015984:Causality; D020878:Device Removal / Q000706:statistics & numerical data; D004938:Esophageal Neoplasms / Q000453:epidemiology* / Q000601:surgery*; D004940:Esophageal Stenosis / Q000453:epidemiology* / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D015995:Prevalence; D011474:Prosthesis Design; D056910:Republic of Korea / Q000453:epidemiology; D015607:Stents / Q000706:statistics & numerical data*; D016896:Treatment Outcome
chemical_list: D008670:Metals