title: A dual-design expandable colorectal stent for malignant colorectal obstruction: results of a multicenter study.
abstract: OBJECTIVE
  It is known that metal stent placement is safe, easy, and effective for the treatment of malignant colorectal obstruction, but these stents are associated with delayed complications of tumor ingrowth and stent migration. The aim of this study was to prospectively investigate the technical feasibility, clinical effectiveness, and safety of a dual-design colorectal stent (consisting of an outer stent and an inner bare nitinol stent) in patients with malignant colorectal obstruction.
  
  
  METHODS
  Placement of the dual stent using a 4.5-mm stent delivery system was attempted in 151 patients with malignant colorectal obstruction, either before surgery (n = 50) or for palliation (n = 101). Multivariate logistic regression analysis was used to identify risk factors associated with complications.
  
  
  RESULTS
  Stent placement was technically successful in 145/151 patients (96%). Of the patients who had a technically successful placement, bowel obstruction resolved within 2 days after stent placement in 48/50 (96%) of the patients in the bridge-to-surgery group and in 87/95 (92%) of the patients in the palliative group. Perforation occurred in 16 patients, incomplete stent expansion in eight patients, stent migration in four patients, tumor overgrowth in five patients, severe rectal pain in five patients, and bleeding in eight patients. Complete obstruction was the only significant risk factor for perforation (odds ratio 6.88, 95% CI 2.04-23.17, P = 0.002). In the palliative group, the median survival was 152.0 days and the mean survival was 263.8 days.
  
  
  CONCLUSIONS
  The dual stent with a 4.5-mm stent delivery system is easy to insert, safe, and reasonably effective for the palliative treatment of malignant colorectal obstruction. However, a great deal of care is needed in its deployment because of the high rate of perforation.
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. hysong@amc.seoul.kr
authors.forename: H-Y
authors.initials: HY
authors.lastname: Song
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Shin
authors.forename: H-C
authors.initials: HC
authors.lastname: Kim
authors.forename: C S
authors.initials: CS
authors.lastname: Yu
authors.forename: J-C
authors.initials: JC
authors.lastname: Kim
authors.forename: S-G
authors.initials: SG
authors.lastname: Kang
authors.forename: C J
authors.initials: CJ
authors.lastname: Yoon
authors.forename: J Y
authors.initials: JY
authors.lastname: Lee
authors.forename: J H
authors.initials: JH
authors.lastname: Koo
authors.forename: K-H
authors.initials: KH
authors.lastname: Lee
authors.forename: J-K
authors.initials: JK
authors.lastname: Kim
authors.forename: D H
authors.initials: DH
authors.lastname: Kim
authors.forename: T-B
authors.initials: TB
authors.lastname: Shin
authors.forename: G-S
authors.initials: GS
authors.lastname: Jung
authors.forename: Y-M
authors.initials: YM
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000150:complications*; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D005548:Foreign-Body Migration / Q000209:etiology; D006801:Humans; D007415:Intestinal Obstruction / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D007416:Intestinal Perforation / Q000209:etiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010146:Pain / Q000209:etiology; D010166:Palliative Care; D011446:Prospective Studies; D015607:Stents / Q000009:adverse effects; D015996:Survival Rate