title: Comparative prognostic value of epidermal growth factor quantitative protein expression compared with FISH for head and neck squamous cell carcinoma.
abstract: OBJECTIVE
  Epidermal growth factor receptor (EGFR) overexpression correlates with recurrence and with treatment resistance in head and neck squamous cell carcinoma (HNSCC). The aim of this study was to evaluate the relationship of EGFR gene copy number utilizing FISH and protein expression with automated quantitative analysis (AQUA) and to correlate those with patient outcome.
  
  
  METHODS
  A tissue microarray composed of 102 HNSCC treated with (chemo)radiation was constructed and analyzed for EGFR copy number by FISH (Vysis; Abbott Laboratories) and EGFR protein expression using AQUA analysis of EGFR staining scored on a scale of 0 to 255. We evaluated associations of EGFR FISH status and AQUA score with clinicopathologic parameters and survival prognosis.
  
  
  RESULTS
  Eleven (17.2%) of 64 tumors with FISH results showed EGFR high polysomy and/or gene amplification (FISH positive). Protein levels assessed by AQUA in FISH-positive cases were significantly higher (P = 0.04) than in FISH-negative cases. Using the continuous AQUA scores for EGFR expression, AQUA and FISH showed significant agreement (Pearson's ρ = 0.353, P = 0.04). Patients with high tumor EGFR protein expression had inferior 5-year overall survival (27.7%) compared with those with low tumor EGFR expression (54%; P = 0.029). There was no significant association between EGFR FISH status and overall survival (P = 0.201). In the multivariate model, high tumor EGFR protein expression status remained an independent prognostic factor for overall survival (P = 0.047).
  
  
  CONCLUSIONS
  EGFR protein content correlates with gene copy number if protein content is quantitated and automatically analyzed, as with AQUA. EGFR protein levels assessed by AQUA strongly predict for patient outcome in HNSCC, whereas EGFR FISH status does not provide prognostic information.
authors.affiliation: Departments of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA.
authors.forename: Eirini
authors.initials: E
authors.lastname: Pectasides
authors.forename: Theodore
authors.initials: T
authors.lastname: Rampias
authors.forename: Panteleimon
authors.initials: P
authors.lastname: Kountourakis
authors.forename: Clarence
authors.initials: C
authors.lastname: Sasaki
authors.forename: Diane
authors.initials: D
authors.lastname: Kowalski
authors.forename: George
authors.initials: G
authors.lastname: Fountzilas
authors.forename: Thomas
authors.initials: T
authors.lastname: Zaramboukas
authors.forename: David
authors.initials: D
authors.lastname: Rimm
authors.forename: Barbara
authors.initials: B
authors.lastname: Burtness
authors.forename: Amanda
authors.initials: A
authors.lastname: Psyrri
mesh_terms: D002277:Carcinoma / Q000175:diagnosis* / Q000235:genetics* / Q000378:metabolism* / Q000401:mortality; D002294:Carcinoma, Squamous Cell; D004815:Epidermal Growth Factor / Q000032:analysis / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D018628:Gene Dosage; D015972:Gene Expression Regulation, Neoplastic; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000378:metabolism* / Q000401:mortality; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D008297:Male; D018307:Neoplasms, Squamous Cell / Q000175:diagnosis* / Q000235:genetics* / Q000378:metabolism* / Q000401:mortality; D011237:Predictive Value of Tests; D011379:Prognosis; D011506:Proteins / Q000032:analysis; D000077195:Squamous Cell Carcinoma of Head and Neck; D016019:Survival Analysis; D046888:Tissue Array Analysis
chemical_list: D011506:Proteins; D004815:Epidermal Growth Factor