title: [Clinical usefulness of bile cytology obtained from biliary drainage tube for diagnosing cholangiocarcinoma].
abstract: OBJECTIVE
  Biliary drainage is performed in many patients with cholangiocarcinoma (CCA) to relieve obstructive jaundice. For those who have undergone biliary drainage, bile cytology can be easily performed since the access is already achieved. This study aims to determine the clinical usefulness of bile cytology for the diagnosis of CCA and to evaluate factors affecting its diagnostic yield.
  
  
  METHODS
  A total of 766 consecutive patients with CCA underwent bile cytology via endoscopic nasobiliary drainage or percutaneous transhepatic biliary drainage from January 2000 to June 2012. Data were collected by retrospectively reviewing the medical records. We evaluated the diagnostic yield of bile cytology with/without other sampling methods including brush cytology and endobiliary forcep biopsy, and the optimal number of repeated bile sampling. Several factors affecting diagnostic yield were then analyzed.
  
  
  RESULTS
  The sensitivity of bile cytology, endobiliary forceps biopsy, and a combination of both sampling methods were 24.7% (189/766), 74.4% (259/348), and 77.9% (271/348), respectively. The cumulative positive rate of bile sampling increased from 40.7% (77/189) at first sampling to 93.1% (176/189) at third sampling. On multivariate analysis, factors associated with positive bile cytology were perihilar tumor location, intraductal growing tumor type, tumor extent ≥ 20 mm, poorly differentiated grade tumor, and three or more samplings.
  
  
  CONCLUSIONS
  Although bile cytology itself has a low sensitivity in diagnosing CCA, it has an additive role when combined with endobiliary forceps biopsy. Due to the relative ease and low cost, bile cytology can be considered a reasonable complementary diagnostic tool for diagnosing CCA.
authors.affiliation: Department of Internal Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Korea.
authors.forename: Jin Yong
authors.initials: JY
authors.lastname: Kim
authors.forename: Joon Hyuk
authors.initials: JH
authors.lastname: Choi
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Kim
authors.forename: Chang Lae
authors.initials: CL
authors.lastname: Kim
authors.forename: Seung Hyeon
authors.initials: SH
authors.lastname: Bae
authors.forename: Young Kwon
authors.initials: YK
authors.lastname: Choi
authors.forename: Yeonjung
authors.initials: Y
authors.lastname: Ha
authors.forename: Min-Joo
authors.initials: MJ
authors.lastname: Song
authors.forename: Jun-Ho
authors.initials: JH
authors.lastname: Choi
authors.forename: Seung-Mo
authors.initials: SM
authors.lastname: Hong
authors.forename: Myung-Hwan
authors.initials: MH
authors.lastname: Kim
mesh_terms: D000368:Aged; D001646:Bile / Q000166:cytology*; D001650:Bile Duct Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D018395:CA-19-9 Antigen / Q000378:metabolism; D018281:Cholangiocarcinoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D004322:Drainage; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011859:Radiography; D012189:Retrospective Studies
chemical_list: D018395:CA-19-9 Antigen