title: Morphologic and Molecular Features of Hepatocellular Adenoma with Gadoxetic Acid-enhanced MR Imaging.
abstract: OBJECTIVE
  To evaluate the diagnostic performance of imaging features of gadoxetic acid-enhanced magnetic resonance (MR) imaging to differentiate among hepatocellular adenoma (HCA) subtypes by using the histopathologic results of the new immunophenotype and genotype classification and to correlate the enhancement pattern on the hepatobiliary phase (HBP) with the degrees of expression of organic anion transporting polypeptide (OATP1B1/3), multidrug resistance-associated protein 2 (MRP) (MRP2), and MRP 3 (MRP3) transporters.
  
  
  METHODS
  This retrospective study was approved by the institutional review board, and the requirement for informed consent waived. MR imaging findings of 29 patients with 43 HCAs were assessed by two radiologists independently then compared with the histopathologic analysis as the standard of reference. Receiver operating characteristic curves and Spearman rank correlation coefficient were used to test the diagnostic performance of gadoxetic acid-enhanced MR imaging features, which included the retention or washout at HBP and degree of transporter expression. Interreader agreement was assessed by using the κ statistic with 95% confidence interval.
  
  
  RESULTS
  The area under the curve for the diagnosis of inflammatory HCA was 0.79 (95% confidence interval: 0.64, 0.90); for the steatotic type, it was 0.90 (95% confidence interval: 0.77, 0.97); and for the β-catenin type, it was 0.87 (95% confidence interval: 0.74, 0.95). There were no imaging features that showed a significant statistical correlation for the diagnosis of unclassified HCAs. On immunohistochemical staining, OATP1B1/3 expression was the main determinant for the retention, whereas MRP3 was the key determinant for washout of gadoxetic acid at HBP (P < .001). MRP2 appeared to have no role.
  
  
  CONCLUSIONS
  Gadoxetic acid-enhanced MR imaging features may suggest the subtype of HCA. The degree of OATP1B1/3 and MRP3 expression correlated statistically with gadoxetic acid retention and washout, respectively, in the HBP.
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Ba-Ssalamah
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Célia
authors.initials: C
authors.lastname: Antunes
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Diana
authors.initials: D
authors.lastname: Feier
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Nina
authors.initials: N
authors.lastname: Bastati
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Jacqueline C
authors.initials: JC
authors.lastname: Hodge
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Judith
authors.initials: J
authors.lastname: Stift
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Cipriano
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Wrba
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Michael
authors.initials: M
authors.lastname: Trauner
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Herold
authors.affiliation: From the Department of Biomedical Imaging and Image-guided Therapy (A.B.S., D.F., N.B., J.C.H., C.J.H.), Department of Pathology (J.S., F.W.), and Division of Gastroenterology and Hepatology, Department of Internal Medicine III (M.T.), Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria; and Clínica Universitária de Radiologia, Faculty of Medicine (C.A., F.C.A.), and Serviço de Anatomia Patológica (M.A.C.), University Hospital of Coimbra, Coimbra, Portugal.
authors.forename: Filipe
authors.initials: F
authors.lastname: Caseiro-Alves
mesh_terms: D018248:Adenoma, Liver Cell / Q000175:diagnosis*; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA