title: Comparison of a newly designed double-layered combination covered stent and D-weave uncovered stent for decompression of obstructive colorectal cancer: a prospective multicenter study.
abstract: OBJECTIVE
  Stent reocclusion and migration are the most important complications after stent insertion. To overcome both problems, a double-layered combination covered stent was developed. Our purpose was to compare the efficacy and safety of the newly designed double-layered combination covered stent (Niti-S enteral colonic stent, Comvi type) and the double-wire woven uncovered stent (Niti-S enteral colonic stent, D-type) in the treatment of malignant colorectal obstructions.
  
  
  METHODS
  Sixty-eight patients with obstructive colorectal cancer underwent stent placement for preoperative decompression (n = 30) or palliative purpose (n = 38) at 6 medical centers. Combination covered stents were used in 31 patients and uncovered stents were used in 37 patients.
  
  
  RESULTS
  There were no significant differences between both stents in terms of technical and clinical success rates. Regarding complications after stent insertion, there was no significant difference in early stent occlusion and migration rate between the combination covered stents and the uncovered stents. Despite a trend toward lower rates of late stent occlusion in the combination covered stent group, there was no significant difference in the rate of late stent occlusion by tumor ingrowth between the 2 groups (0% vs 20%, respectively; P = .107), and late stent migration occurred significantly more often with the combination covered stent (22.2% vs 0%, respectively; P = .041). However, we observed no significant difference in the overall late-complication rates and stent patency duration between the 2 groups.
  
  
  CONCLUSIONS
  In our study, we could not prove that the newly designed double-layered combination covered stents have preventive advantages in stent migration compared with the uncovered stent.
authors.affiliation: Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chang Mo
authors.initials: CM
authors.lastname: Moon
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Kim
authors.forename: Moon Sung
authors.initials: MS
authors.lastname: Lee
authors.forename: Bong Min
authors.initials: BM
authors.lastname: Ko
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Kang-Moon
authors.initials: KM
authors.lastname: Lee
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Byeon
authors.forename: Yong Sik
authors.initials: YS
authors.lastname: Kim
mesh_terms: D000368:Aged; D020099:Coated Materials, Biocompatible; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D019299:Decompression, Surgical / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007415:Intestinal Obstruction / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D008297:Male; D011446:Prospective Studies; D011474:Prosthesis Design; D011860:Radiography, Abdominal; D015607:Stents; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D020099:Coated Materials, Biocompatible