title: Relationships between echo level and histologic characteristics in small hepatocellular carcinomas.
abstract: OBJECTIVE
  The relationships between ultrasound echo level and histologic characteristics of hepatocellular carcinomas (HCCs) of 2 cm or less in diameter were studied.
  
  
  METHODS
  The apparent echo level and frequency-dependent attenuation from the abdominal wall to the tumor and surrounding liver parenchyma were quantitated on B-mode images using diagnostic ultrasound equipment. The inherent echo level corrected by the frequency-dependent attenuation was used in this study. Histologic specimens were collected by sonographically guided small-gauge core-needle biopsy. Increase in deposition of fat and changes in cellular density and in connective tissue density were evaluated histologically.
  
  
  RESULTS
  From the quantitative comparison of echo levels and histologic characteristics, it was evident that the deposition of fat caused an increase in echo levels. A reduction in connective tissue density resulted in a decrease in echo levels in hypoechoic HCCs, which had no or little fat deposition.
  
  
  CONCLUSIONS
  The estimation of echo level in small HCCs may be useful in predicting the tumors' histologic characteristics.
authors.affiliation: Third Department of Internal Medicine, Ehime University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Itoh
authors.forename: K
authors.initials: K
authors.lastname: Akamatsu
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging; D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D003238:Connective Tissue / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D014463:Ultrasonography / Q000379:methods