title: Ultrathin endoscope-assisted self-expandable metallic stent placement following initial unsuccessful attempt in malignant upper gastrointestinal obstruction.
abstract: BACKGROUND
  Conventional endoscopy for self-expandable metallic stent (SEMS) placement may be technically limited in long and tortuous strictures. Therefore, we analyzed the feasibility, safety and usefulness of ultrathin endoscopy (UTE)-guided SEMS placement.
  
  
  METHODS
  This study involved 24 patients with upper gastrointestinal obstruction and unsuccessful initial attempts to place SEMS using conventional endoscopy. After completely passing a UTE across the stricture, the UTE was withdrawn, leaving a guidewire placed via the working channel. Through-the-scope SEMS placement was done using a conventional endoscope inserted along the guidewire. The primary endpoints were assessed by technical/clinical success and stent patency duration.
  
  
  RESULTS
  Stents were successfully placed at target locations in all but one case with a long tortuous stricture, with 95.8% (23/24) technical success. One week after stent placement, mean gastricoutlet obstruction score improved significantly from baseline (1.74 ± 0.62 and 0.33 ± 0.48, respectively; P < 0.001). Stent migration, restenosis, and fracture occurred in four (17.4%), six (26.1%), and one (4.3%) of 23 stents, respectively. Median stent patency duration was 79 days. Mean stent patency was significantly longer in patients who received palliative chemotherapy than in those who did not (122.9 ± 11.0 and 38.3 ± 4.6, respectively; P < 0.001).
  
  
  CONCLUSIONS
  UTE guidance SEMS delivery can be a feasible and safe rescue treatment method for malignant upper gastrointestinal obstruction in cases of failed attempts to place SEMS using conventional endoscopy. Our result warrants a further study to define the efficacy of this method in difficult SEMS placement cases.
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Se Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Hyuk
authors.initials: H
authors.lastname: Lee
authors.forename: Jun Chul
authors.initials: JC
authors.lastname: Park
authors.forename: Sung Kwan
authors.initials: SK
authors.lastname: Shin
authors.forename: Sang Kil
authors.initials: SK
authors.lastname: Lee
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Lee
mesh_terms: D020776:Endoscopes, Gastrointestinal; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000150:complications / Q000175:diagnosis / Q000601:surgery*; D006801:Humans; D007415:Intestinal Obstruction / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010166:Palliative Care / Q000379:methods*; D011446:Prospective Studies; D012086:Reoperation; D012189:Retrospective Studies; D015607:Stents; D014057:Tomography, X-Ray Computed; D017211:Treatment Failure; D041742:Upper Gastrointestinal Tract / Q000601:surgery*
keywords: malignant gastrointestinal obstruction; self-expandable metallic stent (SEMS); ultrathin endoscopy