title: Diagnosis of bile duct cancer by bile cytology: usefulness of post-brushing biliary lavage fluid.
abstract: BACKGROUND
  Pathologic evidence of biliary diseases can be obtained from cytology in addition to endoscopic retrograde cholangiopancreatography (ERCP); however, the diagnostic effectiveness is not satisfactory.
  
  
  OBJECTIVE
  This retrospective, single-center study evaluated the efficacy of various sampling methods for the cytologic diagnosis of bile duct cancer.
  
  
  METHODS
  Biliary samples included bile that was simply aspirated, brush smear, brush-rinsed saline, and post-brushing biliary lavage fluid. A set of samples was compared for cytologic efficacy in 76 patients with surgically proven bile duct cancer and in 50 patients with benign biliary stricture.
  
  
  RESULTS
  The cytologic sensitivity for diagnosing biliary cancer was 34 % with aspirated bile, 32 % with brush smear, 43 % with brush-rinsed saline, and 70 % with post-brushing biliary lavage fluid, in contrast to the null false-positive result in the benign cases. The sensitivity of cytology was significantly higher with post-brushing lavage fluid than with the other three sampling methods (P < 0.0001), and post-brushing lavage fluid improved the cumulative sensitivity by 24 % (P = 0.002). The sensitivity of biliary cytology was also associated with the amount of aspirated bile (P = 0.01) and with the aspiration site (P = 0.03). The rate of cancer positivity in a cytology set differed according to the tumor macroscopic type (85 % in the protruding type vs. 40 % in the flat type; P = 0.003), and according to the size of the cancer (87 % for tumors ≥ 50 mm vs. 66 % for tumors < 50 mm; P = 0.02).
  
  
  CONCLUSIONS
  Post-brushing biliary lavage fluid cytology provides superior diagnostic efficacy, and its addition to ERCP procedures is recommended for obtaining cytologic evidence of bile duct cancer.
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Sugimoto
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsubayashi
authors.affiliation: Division of Molecular Biology and Biochemistry, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kimura
authors.affiliation: Division of Pathology, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Sasaki
authors.affiliation: Division of Pathology, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Nagata
authors.affiliation: Division of Pathology, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Sachiyo
authors.initials: S
authors.lastname: Ohno
authors.affiliation: Division of Hepato-Biliary-Pancreatic Surgery, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Uesaka
authors.affiliation: Division of Clinical Trials, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Mori
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Imai
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Kinichi
authors.initials: K
authors.lastname: Hotta
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Takizawa
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Naomi
authors.initials: N
authors.lastname: Kakushima
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Kawata
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ono