title: Persistent pulmonary nodular ground-glass opacity at thin-section CT: histopathologic comparisons.
abstract: OBJECTIVE
  To retrospectively compare pure pulmonary ground-glass opacity (GGO) nodules observed on thin-section computed tomography (CT) images with histopathologic findings.
  
  
  METHODS
  The institutional review board approved this study and waived informed consent. Histopathologic specimens were obtained from 53 GGO nodules in 49 patients. CT scans were assessed in terms of nodule size, shape, contour, internal characteristics, and the presence of a pleural tag. The findings obtained were compared with histopathologic results. Differences in thin-section CT findings according to histopathologic diagnoses were analyzed by using the Kruskal-Wallis test or Fisher exact test.
  
  
  RESULTS
  Of 53 nodules in 49 patients (20 men, 29 women; mean age, 54 years; range, 29-78 years), 40 (75%) proved to be broncholoalveolar cell carcinoma (BAC) (n=36) or adenocarcinoma with predominant BAC component (n=4), three (6%) atypical adenomatous hyperplasia, and 10 (19%) nonspecific fibrosis or organizing pneumonia. No significant differences in morphologic findings on thin-section CT scans were found among the three diseases (all P>0.05). A polygonal shape (25%, 10 of 40 nodules) and a lobulated or spiculated margin (45%, 18 of 40) in BAC or adenocarcinoma with predominant BAC component were caused by interstitial fibrosis or infiltrative tumor growth. A polygonal shape and a lobulated or spiculated margin were observed in two (20%) and three (30%) of 10 nodules, respectively, in organizing pneumonia/fibrosis were caused by granulation tissue aligned in a linear manner in perilobular regions with or without interlobular septal thickening.
  
  
  CONCLUSIONS
  About 75% of persistent pulmonary GGO nodules are attributed to BAC or adenocarcinoma with predominant BAC component, and at thin-section CT, these nodules do not manifest morphologic features that distinguish them from other GGO nodules with different histopathologic diagnoses.
authors: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710, Korea.
authors: Ha Young
authors: HY
authors: Kim
authors: Young Mog
authors: YM
authors: Shim
authors: Kyung Soo
authors: KS
authors: Lee
authors: Joungho
authors: J
authors: Han
authors: Chin A
authors: CA
authors: Yi
authors: Yoon Kyung
authors: YK
authors: Kim
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology; D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006965:Hyperplasia; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000000981:diagnostic imaging / Q000473:pathology; D011658:Pulmonary Fibrosis / Q000000981:diagnostic imaging / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*