title: Well-differentiated hepatocellular carcinoma: findings of US, CT, and MR imaging.
abstract: BACKGROUND
  To elucidate the imaging characteristics of well-differentiated hepatocellular carcinomas (HCCs) on ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging.
  
  
  METHODS
  Ultrasonograms, CTs, and MR images of 18 histopathologically proven well-differentiated HCCs in 15 patients were reviewed. The findings of these images were correlated with histopathologic findings.
  
  
  RESULTS
  On US, seven tumors were depicted as a hyperechoic area and eight as a hypoechoic area. Three tumors were not visualized. On precontrast CT, four tumors were depicted as a low-density area, but 14 were not visualized. On conventional contrast-enhanced CT, 12 tumors were depicted as a low-density area but six were not visualized. On T1-weighted MR images, 10 tumors had high signal intensity and two had low signal intensity. Six tumors were not visualized. On T2-weighted MR images, five tumors had high signal intensity and two had low signal intensity. Eleven tumors were not visualized. Tumors with fatty change and/or clear cell formation were frequently hyperechoic on US and hyperintense on T1-weighted MR images.
  
  
  CONCLUSIONS
  Well-differentiated HCCs show different findings on US, CT, and MR imaging. Therefore, reliable diagnosis of well-differentiated HCCs by these imaging techniques may be difficult.
authors.affiliation: Department of Radiology, Yamanashi Hospital, Asahi 3-8-31 Kofu, Yamanashi 400-0025, Japan,
authors.forename: S
authors.initials: S
authors.lastname: Monzawa
authors.forename: K
authors.initials: K
authors.lastname: Omata
authors.forename: N
authors.initials: N
authors.lastname: Shimazu
authors.forename: A
authors.initials: A
authors.lastname: Yagawa
authors.forename: K
authors.initials: K
authors.lastname: Hosoda
authors.forename: T
authors.initials: T
authors.lastname: Araki
mesh_terms: D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography