title: Fat containing HCC: findings on CT and MRI including serial contrast-enhanced imaging.
abstract: OBJECTIVE
  The purpose of this article is to review the spectrum of computed tomography (CT) and magnetic resonance imaging (MRI) findings of fat containing hepatocellular carcinoma (HCC), including serial contrast-enhanced imaging.
  
  
  METHODS
  Imaging findings of 10 fat-containing HCCs on CT (n = 2) or MRI (n = 3) or on both CT and MRI (n = 5) were retrospectively reviewed in 9 patients. Both techniques included serial contrast enhanced imaging in arterial, portal venous, and late venous phases.
  
  
  RESULTS
  On non-contrast CT, fat containing HCC was either homogeneously hypodense (n = 6) or of mixed density (n = 1). The density values ranged between -11 and 9 HU. On MRI, homogenous (n = 4) or heterogeneous (n = 4) signal loss was observed on T1-weighted out-of-phase images as compared to in-phase images. Enhancement patterns on serial contrast-enhanced CT and MRI included: arterial enhancement indistinguishable from the liver with venous wash out (n = 2), arterial capillary blush with venous phase fading (n = 2), and heterogeneous arterial enhancement with unenhanced foci and venous phase wash out of enhancements. Larger lesions had late capsular enhancement.
  
  
  CONCLUSIONS
  Fat containing HCC has spectrum of imaging findings on CT and MRI. MRI with chemical shift technique depicts the fat content. Arterial contrast enhancement with venous washout or fading may help for the diagnosis of HCC in inconclusive cases.
authors.affiliation: Department of Radiology, Saint Louis University School of Medicine, 3635 Vista Ave., St. Louis, MO 63110, USA. ncbalci@gmail.com
authors.forename: N Cem
authors.initials: NC
authors.lastname: Balci
authors.forename: Alex S
authors.initials: AS
authors.lastname: Befeler
authors.forename: B Kirke
authors.initials: BK
authors.lastname: Bieneman
authors.forename: Rana
authors.initials: R
authors.lastname: Fattahi
authors.forename: Sezer
authors.initials: S
authors.lastname: Saglam
authors.forename: Necat
authors.initials: N
authors.lastname: Havlioglu
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging* / Q000473:pathology*; D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007472:Iohexol / Q000031:analogs & derivatives*; D008113:Liver Neoplasms / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide; D019786:Gadolinium DTPA