title: Randomized controlled exploratory study comparing the usefulness of two types of metallic stents with different axial forces for the management of duodenal obstruction caused by pancreatobiliary cancer.
abstract: BACKGROUND
  Very few studies have examined effectiveness of duodenal stent placement (DSP) for duodenal obstruction (DO) caused specifically by pancreatobiliary cancer. We compared two types of stents with different axial forces (AF) for DO with pancreatobiliary cancer.
  
  
  METHODS
  The patients were randomly assigned to two stent groups with different AF (high AF stent, WallFlex™: W-group or low AF stent, Niti-S™: N-group). The primary endpoint was improvement in the Gastric Outlet Obstruction Scoring System (GOOSS) score. This study was registered at UMIN000009061.
  
  
  RESULTS
  The GOOSS scores significantly improved in both W-group (0.9 before vs. 2.7 after; P = 0.002) and N-group (1.0 before vs. 2.5 after; P = 0.001). The change in the GOOSS score after DSP did not differ significantly between the groups (P = 0.482). The median time to recurrent DO (RDO) was significantly shorter in W-group than in N-group (89 days vs. 421 days; P = 0.025). The incidence of RDO was significantly higher in W-group than in N-group (64% vs. 24%; P = 0.027). Stent kinking occurred only in W-group.
  
  
  CONCLUSIONS
  The GOOSS scores significantly improved after DSP, but effectiveness did not differ significantly between groups. The use of stents with high AF was related to short-term stent patency, but did not influence survival time.
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan. kokuwaki@kitasato-u.ac.jp.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Okuwaki
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kida
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamauchi
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imaizumi
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Miyawaza
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Iwai
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Masutani
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Rikiya
authors.initials: R
authors.lastname: Hasegawa
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0374, Japan.
authors.forename: Wasaburo
authors.initials: W
authors.lastname: Koizumi
mesh_terms: D000368:Aged; D001650:Bile Duct Neoplasms / Q000150:complications* / Q000601:surgery; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000379:methods*; D004380:Duodenal Obstruction / Q000209:etiology / Q000601:surgery*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D010166:Palliative Care / Q000379:methods*; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000601:surgery; D011446:Prospective Studies; D011474:Prosthesis Design; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
keywords: Axial force; Duodenal stent placement; Gastric Outlet Obstruction Scoring System score; Pancreatobiliary cancer; Self-expandable metallic stent