title: Differentiation between dysplastic nodule and early-stage hepatocellular carcinoma: the utility of conventional MR imaging.
abstract: OBJECTIVE
  To elucidate the variety of ways early-stage hepatocellular carcinoma (HCC) can appear on magnetic resonance (MR) imaging by analyzing T1-weighted, T2-weighted, and gadolinium-enhanced dynamic studies.
  
  
  METHODS
  Seventy-three patients with well-differentiated HCC (wHCC) or dysplastic nodules were retrospectively identified from medical records, and new histological sections were prepared and reviewed. The tumor nodules were categorized into three groups: dysplastic nodule (DN), wHCC compatible with Edmondson-Steiner grade I HCC (w1-HCC), and wHCC compatible with Edmondson-Steiner grade II HCC (w2-HCC). The signal intensity on pre-contrast MR imaging and the enhancing pattern for each tumor were recorded and compared between the three tumor groups.
  
  
  RESULTS
  Among the 73 patients, 14 were diagnosed as having DN, 40 were diagnosed as having w1-HCC, and 19 were diagnosed as having w2-HCC. Hyperintensity measurements on T2-weighted axial images (T2WI) were statistically significant between DNs and wHCC (P = 0.006) and between DN and w1-HCC (P = 0.02). The other imaging features revealed no significant differences between DN and wHCC or between DN and w1-HCC. Hyperintensity on both T1W out-phase imaging (P = 0.007) and arterial enhancement on dynamic study (P = 0.005) showed statistically significant differences between w1-HCC and w2-HCC. The other imaging features revealed no significant differences between w1-HCC and w2-HCC.
  
  
  CONCLUSIONS
  In the follow-up for a cirrhotic nodule, increased signal intensity on T2WI may be a sign of malignant transformation. Furthermore, a noted loss of hyperintensity on T1WI and the detection of arterial enhancement might indicate further progression of the histological grade.
authors.affiliation: Chen-Te Chou, Ran-Chou Chen, Department of Biomedical Imaging and Radiological Science, National Yang-Ming Medical University, Taipei 112, Taiwan.
authors.forename: Chen-Te
authors.initials: CT
authors.lastname: Chou
authors.forename: Jung-Mao
authors.initials: JM
authors.lastname: Chou
authors.forename: Ting-An
authors.initials: TA
authors.lastname: Chang
authors.forename: Shiu-Feng
authors.initials: SF
authors.lastname: Huang
authors.forename: Chia-Bang
authors.initials: CB
authors.lastname: Chen
authors.forename: Yao-Li
authors.initials: YL
authors.lastname: Chen
authors.forename: Ran-Chou
authors.initials: RC
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D006528:Carcinoma, Hepatocellular / Q000150:complications / Q000473:pathology*; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D003287:Contrast Media; D003937:Diagnosis, Differential; D018450:Disease Progression; D055088:Early Detection of Cancer; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008103:Liver Cirrhosis / Q000150:complications / Q000473:pathology*; D008113:Liver Neoplasms / Q000150:complications / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA
keywords: Dysplastic nodule; Hepatocellular carcinoma; Histological grading; Magnetic resonance imaging; Well-differentiated hepatocellular carcinoma