title: Ground-glass opacity on thin-section CT: value in differentiating subtypes of adenocarcinoma of the lung.
abstract: OBJECTIVE
  The purpose of this study was to determine whether thin-section CT could be used to differentiate small localized bronchioloalveolar carcinoma from peripheral adenocarcinoma having a bronchioloalveolar (replacement) growth pattern of alveolar lining cells and from adenocarcinoma not having a replacement growth pattern on the basis of the extent of ground-glass opacity revealed by thin-section CT.
  
  
  METHODS
  One hundred twenty-four small, surgically resected, peripheral adenocarcinomas from 119 patients (67 men and 52 women; mean age, 60 years) were studied. Lesion diameters were 0.4-2.0 cm (median, 1.5 cm). The extent of ground-glass opacity within lesions on preoperative thin-section CT was reviewed retrospectively by three thoracic radiologists. On the basis of replacement growth of alveolar lining cells, small adenocarcinomas were classified histologically as localized bronchioloalveolar carcinomas (n = 42) or as adenocarcinomas with (n = 53) or without (n = 29) a replacement growth pattern of alveolar lining cells.
  
  
  RESULTS
  The percentage of lesions that had ground-glass opacity was significantly greater in localized bronchioloalveolar carcinomas (mean, 56.7%+/-33.0%) than in adenocarcinomas with a replacement growth pattern (mean, 26.3%+/-25.3%, p < .001) or in adenocarcinomas without a replacement growth pattern (mean, 8.3%+/-4.7%, p < .001).
  
  
  CONCLUSIONS
  Determination of the ground-glass opacity area in each tumor as revealed on thin-section CT was useful for differentiating small localized bronchioloalveolar carcinomas from small adenocarcinomas not having a replacement growth pattern.
authors.affiliation: Department of Diagnostic Radiology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Higashinari, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kuriyama
authors.forename: M
authors.initials: M
authors.lastname: Seto
authors.forename: T
authors.initials: T
authors.lastname: Kasugai
authors.forename: M
authors.initials: M
authors.lastname: Higashiyama
authors.forename: S
authors.initials: S
authors.lastname: Kido
authors.forename: Y
authors.initials: Y
authors.lastname: Sawai
authors.forename: K
authors.initials: K
authors.lastname: Kodama
authors.forename: C
authors.initials: C
authors.lastname: Kuroda
mesh_terms: D000230:Adenocarcinoma / Q000145:classification / Q000000981:diagnostic imaging*; D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000145:classification / Q000000981:diagnostic imaging; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D008175:Lung Neoplasms / Q000145:classification / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data