title: Relationships between EGFR mutation status of lung cancer and preoperative factors - are they predictive?
abstract: BACKGROUND
  The epidermal growth factor receptor (EGFR) mutation status of lung cancer is important because it means that EGFR-tyrosine kinase inhibitor treatment is indicated. The purpose of this prospective study is to determine whether EGFR mutation status could be identified with reference to preoperative factors.
  
  
  METHODS
  One hundred-forty eight patients with lung cancer (111 adenocarcinomas, 25 squamous cell carcinomas and 12 other cell types) were enrolled in this study. The EGFR mutation status of each lung cancer was analyzed postoperatively.
  
  
  RESULTS
  There were 58 patients with mutant EGFR lung cancers (mutant LC) and 90 patients with wild-type EGFR lung cancers (wild-type LC). There were significant differences in gender, smoking status, maximum tumor diameter in chest CT, type of tumor shadow, clinical stage between mutant LC and wild-type LC. EGFR mutations were detected only in adenocarcinomas. Maximum standardized uptake value (SUVmax:3.66±4.53) in positron emission tomography-computed tomography of mutant LC was significantly lower than that (8.26±6.11) of wild-type LC (p<0.0001). Concerning type of tumor shadow, the percentage of mutant LC was 85.7% (6/7) in lung cancers with pure ground glass opacity (GGO), 65.3%(32/49) in lung cancers with mixed GGO and 21.7%(20/92) in lung cancers with solid shadow (p<0.0001). For the results of discriminant analysis, type of tumor shadow (p=0.00036) was most significantly associated with mutant EGFR. Tumor histology (p=0.0028), smoking status (p=0.0051) and maximum diameter of tumor shadow in chest CT (p=0.047) were also significantly associated with mutant EGFR. The accuracy for evaluating EGFR mutation status by discriminant analysis was 77.0% (114/148).
  
  
  CONCLUSIONS
  Mutant EGFR is significantly associated with lung cancer with pure or mixed GGO, adenocarcinoma, never-smoker, smaller tumor diameter in chest CT. Preoperatively, EGFR mutation status can be identified correctly in about 77 % of lung cancers.
authors.affiliation: Department of Thoracic Surgery, Kanazawa Medical University, Daigaku, Uchinada, Ishikawa, Japan E-mail : usuda@kanazawa-med.ac.jp.
authors.forename: Katsuo
authors.initials: K
authors.lastname: Usuda
authors.forename: Motoyasu
authors.initials: M
authors.lastname: Sagawa
authors.forename: Nozomu
authors.initials: N
authors.lastname: Motono
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Ueno
authors.forename: Makoto
authors.initials: M
authors.lastname: Tanaka
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Machida
authors.forename: Munetaka
authors.initials: M
authors.lastname: Matoba
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Taniguchi
authors.forename: Hisao
authors.initials: H
authors.lastname: Tonami
authors.forename: Yoshimichi
authors.initials: Y
authors.lastname: Ueda
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sakuma
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D002288:Adenocarcinoma, Mucinous / Q000235:genetics* / Q000473:pathology; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics; D018287:Carcinoma, Large Cell / Q000235:genetics* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D009154:Mutation / Q000235:genetics*; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011300:Preoperative Care; D011379:Prognosis; D015996:Survival Rate; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; C512478:EGFR protein, human; D066246:ErbB Receptors