title: Intraductal US in the assessment of tumor involvement to the orifice of the cystic duct by malignant biliary obstruction.
abstract: BACKGROUND
  Tumor involvement to the orifice of the cystic duct (OCD) is a risk factor for cholecystitis after metallic stent (MS) placement.
  
  
  OBJECTIVE
  ERCP and intraductal US (IDUS) were used to assess tumor involvement to the OCD.
  
  
  METHODS
  A prospective consecutive study.
  
  
  METHODS
  The University of Tokyo Hospital, Japan.
  
  
  METHODS
  Between January 2003 and May 2007, 34 patients with resectable malignant biliary obstruction underwent an ERCP and an IDUS before preoperative biliary drainage.
  
  
  METHODS
  ERCP and IDUS findings were confirmed via a histopathologic analysis of surgical specimens.
  
  
  RESULTS
  An ERCP showed that the cystic duct was opacified in 22 of 34 patients (64.7%). Eight patients were diagnosed with OCD tumor involvement. In the remaining 12 patients, tumor involvement was impossible to evaluate via an ERCP. An IDUS identified tumor involvement to the OCD in all 34 patients. Tumor involvement to the OCD was diagnosed in 12 patients, including 4 patients with previously negative results during an ERCP. Tumor involvement was confirmed by histopathology of surgical specimens. The sensitivity and specificity of detection were 66.7% (8/12) and 63.6% (14/22), respectively, via ERCP, and 100% (12/12) and 100% (22/22), respectively, via IDUS.
  
  
  CONCLUSIONS
  The small sample size.
  
  
  CONCLUSIONS
  IDUS, in addition to ERCP, provides an accurate evaluation of tumor involvement to the OCD in patients with malignant biliary obstruction.
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Nakai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Isayama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tsujino
authors.forename: Takao
authors.initials: T
authors.lastname: Kawabe
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yashima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yagioka
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Kogure
authors.forename: Takashi
authors.initials: T
authors.lastname: Sasaki
authors.forename: Osamu
authors.initials: O
authors.lastname: Togawa
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Arizumi
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Ito
authors.forename: Saburou
authors.initials: S
authors.lastname: Matsubara
authors.forename: Kenji
authors.initials: K
authors.lastname: Hirano
authors.forename: Naoki
authors.initials: N
authors.lastname: Sasahira
authors.forename: Minoru
authors.initials: M
authors.lastname: Tada
authors.forename: Masao
authors.initials: M
authors.lastname: Omata
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000379:methods*; D001651:Cholestasis, Extrahepatic / Q000175:diagnosis* / Q000601:surgery; D003138:Common Bile Duct Neoplasms / Q000175:diagnosis* / Q000601:surgery; D003549:Cystic Duct / Q000473:pathology*; D019160:Endosonography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity