title: Newly developed hepatocellular carcinoma (HCC) in chronic liver disease: MR imaging findings before the diagnosis of HCC.
abstract: OBJECTIVE
  The purpose of this work was to describe the initial magnetic resonance (MR) imaging findings obtained before an imaging diagnosis of overt hepatocellular carcinoma (HCC) in the chronically damaged liver.
  
  
  METHODS
  One hundred fifty-two newly diagnosed HCCs diagnosed by dynamic computed tomography (n = 111) or by MR imaging (n = 41), in addition to digital subtraction hepatic arteriography, in 96 patients were subjected to analysis of their MR imaging features within the previous 2 years.
  
  
  RESULTS
  Ninety-seven (64%) HCC cases showed no focal lesions distinguishable from background hepatic parenchyma in MR images taken before the indication of typical HCC. The remaining 55 (36%) lesions were readily identified in earlier images and were categorized into 3 groups: nonhypervascular lesions (category I, n = 6), lesions with partially hypervascular foci of "nodule-within-nodule" appearance (category II, n = 12), and homogeneously hypervascular and/or T2-weighted hyperintense lesions (category III, n = 37). The size and doubling time of category III lesions (0.7 cm, 154 days) were smaller and shorter than those of the other lesions (1.2 cm, 377 days).
  
  
  CONCLUSIONS
  Before the imaging diagnosis of HCCs, the premalignant or early malignant lesions can be found on the prior MR images just in the minority of the lesions in the cirrhotic liver.
authors.affiliation: Department of Diagnostic Radiology and the Research Institute of Radiological Science, Yonsei University College of Medicine, YongDong Severance Hospital, Seoul, South Korea.
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Yu
authors.forename: Eun-Suk
authors.initials: ES
authors.lastname: Cho
authors.forename: Ki-Hong
authors.initials: KH
authors.lastname: Kim
authors.forename: Woo-Suk
authors.initials: WS
authors.lastname: Chung
authors.forename: Mi-Suk
authors.initials: MS
authors.lastname: Park
authors.forename: Ki Whang
authors.initials: KW
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000379:methods; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media / Q000008:administration & dosage; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology; D008107:Liver Diseases / Q000175:diagnosis* / Q000473:pathology; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011230:Precancerous Conditions / Q000175:diagnosis* / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA