title: Intraductal ultrasonography for hepatocellular carcinoma with tumor thrombi in the bile duct: comparison with polypoid cholangiocarcinoma.
abstract: OBJECTIVE
  Tumor thrombi in the bile duct caused by hepatocellular carcinoma (HCC), and cholangiocarcinoma show polypoid lesions on cholangiographic findings. This study prospectively compared the images of intraductal ultrasonography between HCC and polypoid cholangiocarcinoma.
  
  
  METHODS
  In five patients with tumor thrombi in the bile duct caused by HCC, a 2.0 mm diameter ultrasonic probe with a frequency of 20 MHz was inserted into the bile duct via the transpapillary route (n = 4) or the transhepatic route (n = 1). The images were compared to that of 65 patients with cholangiocarcinoma.
  
  
  RESULTS
  In all patients with HCC, intraductal ultrasonography showed a 'polypoid tumor with a narrow base'. In 16 of 65 patients with cholangiocarcinoma, it showed a 'polypoid tumor with a narrow base'. When intraductal ultrasonography showed a 'polypoid tumor with a narrow base', the findings of a positive 'nodule within a nodule' (40 vs 0%; P < 0.05), and the absence of a 'papillary-surface pattern' (80 vs 13%; P < 0.05) were more highly associated with tumor thrombi caused by HCC than to polypoid-type cholangiocarcinoma.
  
  
  CONCLUSIONS
  Intraductal ultrasonography was useful to distinguish between tumor thrombi caused by HCC and polypoid-type cholangiocarcinoma.
authors.affiliation: Department of Gastroenterology, Jichi Medical School, Yakushiji, Tochigi, Japan. tamadaki@jichi.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Tamada
authors.forename: N
authors.initials: N
authors.lastname: Isoda
authors.forename: S
authors.initials: S
authors.lastname: Wada
authors.forename: T
authors.initials: T
authors.lastname: Tomiyama
authors.forename: A
authors.initials: A
authors.lastname: Ohashi
authors.forename: Y
authors.initials: Y
authors.lastname: Satoh
authors.forename: K
authors.initials: K
authors.lastname: Ido
authors.forename: K
authors.initials: K
authors.lastname: Sugano
mesh_terms: D000368:Aged; D001650:Bile Duct Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D001652:Bile Ducts / Q000473:pathology*; D001653:Bile Ducts, Intrahepatic; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D018281:Cholangiocarcinoma / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D011127:Polyps / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D018084:Ultrasonography, Interventional