title: The prognostic significance of HER2 overexpression in non-small cell lung cancer.
abstract: OBJECTIVE
  The human epidermal growth factor receptor HER-2/neu (HER2) gene is a proto-oncogene involved in the signal transduction pathways leading to cell growth and differentiation. The present study focused on the clinical significance of the expression of HER2 in non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Consecutive specimens of 159 adenocarcinomas and 77 squamous cell carcinomas, from patients who had been treated by complete resection of NSCLC in our department between 2003 and 2005, were studied. The HER2 expression was evaluated by immunohistochemical staining with score of membranous staining being 0=none, 1=weak, 2=10-30% cells, 3≥30% cells stained.
  
  
  RESULTS
  The staining scores in adenocarcinoma were 0 in 121 patients (76.1%), 1 in 16 (10.0%), 2 in 17 (10.7%), and 3 in 5 patients (3.1%). The HER2 expression scores in squamous cell carcinoma were 0 in 74 patients (96.1%), 1 in 1 (1.2%), 2 in 1 (1.2%), and 3 in 1 patient (1.2%). The postoperative 5-year survival rate of patients with adenocarcinoma according to the expression of HER2 scores 0, 1, 2 and 3 was 75.3%, 77.8%, 76.5% and 20.0%, respectively. Patients with adenocarcinoma with score 3 staining had a significantly unfavorable prognosis compared to those with staining scores of 0-2 (p=0.0216).
  
  
  CONCLUSIONS
  HER2 overexpression (score 3) in adenocaricinoma was a significantly unfavorable prognostic factor. Since the number of NSCLC patients with HER2 overexpression was small, further investigations will be necessary to clarify the efficacy of molecular targeted therapy for this subgroup.
authors.affiliation: Second Department of Surgery, School of Medicine, University of Occupational and Environmental Health, Yahatanishi, Kitakyushu 807, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Takenaka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hanagiri
authors.forename: Shinji
authors.initials: S
authors.lastname: Shinohara
authors.forename: Taiji
authors.initials: T
authors.lastname: Kuwata
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Chikaishi
authors.forename: Soich
authors.initials: S
authors.lastname: Oka
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Shigematsu
authors.forename: Yoshika
authors.initials: Y
authors.lastname: Nagata
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Shimokawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakagawa
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Uramoto
authors.forename: Tomoko
authors.initials: T
authors.lastname: So
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Tanaka
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D018734:Genes, erbB-2; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008175:Lung Neoplasms / Q000378:metabolism* / Q000601:surgery; D008297:Male; D011379:Prognosis; D000090063:Proto-Oncogene Mas; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis* / Q000235:genetics*; D015398:Signal Transduction; D016896:Treatment Outcome
chemical_list: D000090063:Proto-Oncogene Mas; D018719:Erb-b2 Receptor Tyrosine Kinases; C000715470:MAS1 protein, human; C508053:ERBB2 protein, human