title: Correlation between epidermal growth factor receptor mutations and expression of female hormone receptors in East-Asian lung adenocarcinomas.
abstract: BACKGROUND
  Epidermal growth factor receptor (EGFR) mutations are more common in lung adenocarcinoma and in female patients of East-Asian origin. We aimed to assess the expression of female hormone receptors in East-Asian lung adenocarcinomas, their correlation with EGFR mutations, and prognostic significance.
  
  
  METHODS
  Estrogen receptor (ER)alpha, ERbeta, progesterone receptor (PR), and Her-2 expression were examined using immunohistochemical methods on 109 lung adenocarcinoma cases. EGFR mutations were analyzed by partially denaturing high performance liquid chromatography. Association of hormone receptor with clinical factors was assessed using the Fisher's exact test. Associations with survival were assessed using the Cox proportional hazard model.
  
  
  RESULTS
  Using scoring criteria routinely used for breast cancer, there were four (4%) ERalpha, one (1%) ERbeta, six (6%) PR, and one (1%) Her-2 positive cases. Considering any staining as positive, 14 (14%) ERalpha, 10 (9%) ERbeta, 12 (12%) PR, and 26 (24%) Her-2 cases were positive. Thirty-nine patients (39%) had EGFR mutations. ERalpha positivity was significantly associated with ERbeta and PR positivity. There were more EGFR mutations seen in tumors with ERbeta positivity (60%) compared with those with negative expression (37.9%), and there was a trend toward a poorer outcome for patients with tumor that were positive for ERbeta and Her-2.
  
  
  CONCLUSIONS
  We found that ERalpha, ERbeta, PR, and Her-2 expression in lung adenocarcinoma are present but limited. This suggests that hormonal influence may not be an important factor to account for the high prevalence of lung cancer among the East-Asian women.
authors.affiliation: Department of Medical Oncology, National Cancer Centre, Singapore. dmotck@nccs.com.sg
authors.forename: Chee-Keong
authors.initials: CK
authors.lastname: Toh
authors.forename: Baidah
authors.initials: B
authors.lastname: Ahmad
authors.forename: Richie
authors.initials: R
authors.lastname: Soong
authors.forename: Khoon-Leong
authors.initials: KL
authors.lastname: Chuah
authors.forename: Sze-Huey
authors.initials: SH
authors.lastname: Tan
authors.forename: Siew-Wan
authors.initials: SW
authors.lastname: Hee
authors.forename: Swan-Swan
authors.initials: SS
authors.lastname: Leong
authors.forename: Eng-Huat
authors.initials: EH
authors.lastname: Tan
authors.forename: Wan-Teck
authors.initials: WT
authors.lastname: Lim
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism; D016022:Case-Control Studies; D066246:ErbB Receptors / Q000235:genetics*; D005202:Asia, Eastern; D005260:Female; D005838:Genotype; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D012307:Risk Factors; D015996:Survival Rate
chemical_list: D066246:ErbB Receptors; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C512478:EGFR protein, human; C508053:ERBB2 protein, human