title: Evaluation of liver tumors using acoustic radiation force impulse elastography and correlation with histologic data.
abstract: OBJECTIVE
  Acoustic radiation force impulse (ARFI) technology represents an innovative method for the quantification of tissue elasticity. The aims of this study were to evaluate elasticity by ARFI in both liver tumors and background liver tissue and to compare ARFI measurements with histologic data in liver tumors and background liver.
  
  
  METHODS
  Seventy-nine tumors were prospectively studied: 43 benign and 36 malignant. Acoustic radiation force impulse measurements for each tumor type were expressed as mean ± standard deviation for both liver tumors and background liver; ARFI data were also correlated with histologic data.
  
  
  RESULTS
  For liver tumors, the mean stiffness values were 1.90 ± 0.86 m/s for hepatocellular adenoma (n = 9), 2.14 ± 0.49 m/s for hemangioma (n = 15), 3.14 ± 0.63 m/s for focal nodular hyperplasia (n = 19), 2.4 ± 1.01 m/s for hepatocellular carcinoma (n = 24), and 3.0 ± 1.36 m/s for metastasis (n = 12). Important variations were observed within each tumor type or within a single tumor. These variations could have been due to necrosis, hemorrhage, or colloid. There was no statistically significant difference between the benign and malignant groups. Regarding background liver, it was possible to observe pathologic abnormalities in histologic analyses or liver function tests to explain the ARFI data. The degree of fibrosis was not the only determinant of liver stiffness in background liver; other factors such as portal embolization, sinusoidal obstruction syndrome caused by chemotherapy, and cholestasis, also could have interfered.
  
  
  CONCLUSIONS
  Acoustic radiation force impulse elastography could not allow differentiation between benign and malignant tumors. This study provides a better understanding of the correlation between ARFI and histologic data for both tumors and background liver.
authors.affiliation: Department of Radiology, Saint Andre Hospital, Centre Hospitalier Universitaire de Bordeaux, 1 rue Jean Burguet, 33075 Bordeaux, France. norafrulio@yahoo.fr
authors.forename: Nora
authors.initials: N
authors.lastname: Frulio
authors.forename: Herve
authors.initials: H
authors.lastname: Laumonier
authors.forename: Thibault
authors.initials: T
authors.lastname: Carteret
authors.forename: Christophe
authors.initials: C
authors.lastname: Laurent
authors.forename: Florent
authors.initials: F
authors.lastname: Maire
authors.forename: Charles
authors.initials: C
authors.lastname: Balabaud
authors.forename: Paulette
authors.initials: P
authors.lastname: Bioulac-Sage
authors.forename: Herve
authors.initials: H
authors.lastname: Trillaud
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies