title: Epidermal growth factor receptor mutation in lung adenocarcinomas: relationship with CT characteristics and histologic subtypes.
abstract: OBJECTIVE
  To retrospectively identify quantitative computed tomographic (CT) features that correlate with epidermal growth factor receptor (EGFR) mutation in surgically resected lung adenocarcinomas stratified by the International Association for the Study of Lung Cancer (IASLC), American Thoracic Society (ATS), and European Respiratory Society (ERS) classification in an East Asian cohort of patients known to have a high prevalence of EGFR mutations.
  
  
  METHODS
  An institutional review board approved this study and waived informed consent. In 153 surgically resected lung adenocarcinomas, EGFR mutation was determined by direct DNA sequencing. Histologic subtype was classified according to IASLC/ATS/ERS classification of lung adenocarcinoma. At preoperative chest CT, the percentage of ground-glass opacity (GGO) volume and total tumor volume of each tumor were measured by using a semiautomated algorithm. Distribution of EGFR mutation according to histologic subtype, percentage of GGO volume, and total tumor volume was evaluated by using the Fisher exact test, the Student t test, trend analysis, and multiple logistic regression analysis.
  
  
  RESULTS
  Exon 21 missense mutation was more frequent in lepidic predominant adenocarcinomas than in other histologic subtypes (odds ratio, 3.44; 95% confidence interval: 1.53, 7.74; P = .003). GGO volume percentage in tumors with exon 21 missense mutation (61.7% ± 31.9 [standard deviation]) was significantly higher than that in EGFR wild-type tumors (30.0% ± 38.5) (P = .0001) and exon 19-mutated tumors (28.9% ± 37.7) (P = .0006). A significant trend of prevalence of exon 21 missense mutation increasing along with increasing GGO volume (P = .0008) was found.
  
  
  CONCLUSIONS
  GGO volume percentage in tumors with exon 21 missense mutation was significantly higher than that in tumors with other EGFR mutation status. This can be related to the fact that exon 21 missense mutation was significantly more frequent in lepidic predominant adenocarcinomas, including adenocarcinoma in situ, minimally invasive adenocarcinoma, and lepidic predominant invasive adenocarcinoma, according to IASLE/ATS/ERS classification.
authors.affiliation: Department of Radiology, Seoul National University Hospital, 28 Yeongeon-dong, Chongno-gu, Seoul 110-744, Republic of Korea. eehyunju00@gmail.com
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Lee
authors.forename: Young Tae
authors.initials: YT
authors.lastname: Kim
authors.forename: Chang Hyun
authors.initials: CH
authors.lastname: Kang
authors.forename: Binsheng
authors.initials: B
authors.lastname: Zhao
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Tan
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Schwartz
authors.forename: Thorsten
authors.initials: T
authors.lastname: Persigehl
authors.forename: Yoon Kyung
authors.initials: YK
authors.lastname: Jeon
authors.forename: Doo Hyun
authors.initials: DH
authors.lastname: Chung
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000235:genetics* / Q000473:pathology; D000465:Algorithms; D016009:Chi-Square Distribution; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D066246:ErbB Receptors