title: Brain metastasis features and association with tumor epidermal growth factor receptor mutation in patients with adenocarcinoma of the lung.
abstract: OBJECTIVE
  Epidermal growth factor receptor (EGFR) mutations are frequent in pulmonary adenocarcinoma patients. The association between tumor EGFR mutation and characteristics of brain metastasis (BM) is still unclear.
  
  
  METHODS
  We retrospectively reviewed pulmonary adenocarcinoma patients with and without BMs, and characteristics of BM to analyze the association between tumor EGFR mutation and characteristics of BM.
  
  
  RESULTS
  Of 374 cases, 239 had EGFR mutations; 69 had BM at initial diagnosis, and 82 with BMs after treatment. All eligible patients received EGFR-tyrosine kinase inhibitors treatment. Older patients (≥70 years old) were less likely to have BMs than younger patients (25.8% vs 48%, P < 0.001). Patients with higher N stage had higher proportion of BMs (P = 0.006). Patients with exon 19 deletion were more likely to have BMs than those without EGFR mutation (48.1% vs 34.1%, P = 0.021). Patients with exon 19 deletion didn't have significantly higher chance of BMs at initial diagnosis but had higher chance to develop BM after treatment than those without EGFR mutation (35.6% vs 21.2%, P = 0.019). Patients with exon 19 deletion survived longer than those without EGFR mutation (1-year survival rate 95.8% vs 78.7%, P = 0.003). Thus, longer survival may lead to higher proportion of BM occurrence in patients with exon 19 deletion than those without EGFR mutation.
  
  
  CONCLUSIONS
  In pulmonary adenocarcinoma, there is no significant difference in frequency of BMs at initial diagnosis between patients with EGFR mutation and wild type. However, after treatment, patients with EGFR mutations are significantly more likely to develop BM.
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taiwan, Republic of China.|School of Medicine, National Yang-Ming University, Taiwan, Republic of China.
authors.forename: Yung-Hung
authors.initials: YH
authors.lastname: Luo
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taiwan, Republic of China.|School of Medicine, National Yang-Ming University, Taiwan, Republic of China.
authors.forename: Chieh-Hung
authors.initials: CH
authors.lastname: Wu
authors.affiliation: Hsinchu Mackay Memorial Hospital, Taiwan, Republic of China.
authors.forename: Chu-Yun
authors.initials: CY
authors.lastname: Huang
authors.affiliation: Taipei Tzu Chi Hospital, Taiwan, Republic of China.
authors.forename: Chih-Wei
authors.initials: CW
authors.lastname: Wu
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taiwan, Republic of China.|School of Medicine, National Yang-Ming University, Taiwan, Republic of China.
authors.forename: Wen-Shuo
authors.initials: WS
authors.lastname: Wu
authors.affiliation: Sijhih Cathay General Hospital, Taiwan, Republic of China.
authors.forename: Yu-Chin
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Taipei Cancer Center, College of Medical Science and Technology, Taipei Medical University, Taiwan, Republic of China.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Whang-Peng
authors.affiliation: Department of Chest Medicine, Taipei Veterans General Hospital, Taiwan, Republic of China.|School of Medicine, National Yang-Ming University, Taiwan, Republic of China.|Taipei Cancer Center, College of Medical Science and Technology, Taipei Medical University, Taiwan, Republic of China.
authors.forename: Yuh-Min
authors.initials: YM
authors.lastname: Chen
mesh_terms: D000230:Adenocarcinoma / Q000150:complications* / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000473:pathology / Q000556:secondary*; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D066246:ErbB Receptors
keywords: adenocarcinoma of the lungs; brain metastasis; exon 19 deletion; lymph node; tumor epidermal growth factor receptor