title: Expression of cyclooxygenase-2 and epidermal growth factor receptor in primary and recurrent glioblastoma multiforme.
abstract: OBJECTIVE
  To investigate the pattern and level of cyclooxygenase-2 (COX-2) expression in a series of high grade primary and recurrent glioblastoma multiforme (GBM) and correlation with time to recurrence and patients' survival following therapy. The relationship between COX-2 and epidermal growth factor receptor (EGFR) immunoreactivities was evaluated.
  
  
  METHODS
  Specimens of 14 primary and 14 recurrent GBMs (eight pairs) following surgery and full course radiation therapy were processed for immunostaining on COX-2 and EGFR. Tumor cell positivity was semi-quantitatively scored. COX-2 scores of the primary tumor and recurrence were correlated with the time to radiological tumor progression and patients' survival.
  
  
  RESULTS
  COX-2 positive tumor cells were disseminated throughout the tumor parenchyma. The intensity and pattern of COX-2 expression were heterogeneous, with predominant expression in areas surrounding tumor necrosis. Scoring of COX-2 positivity revealed values between 1 and 80% of the cells. Primary GBMs with COX-2 expression levels between 25% and 70% of the tumor cells showed a shorter time to radiological recurrence than GBMs with <10% COX-2 positive tumor cells (respectively, 219 +/- 50 and 382 +/- 77 days). No correlation was found between the COX-2 expression in the primary tumor and patients' survival (r (s) = -0.073) following therapy. No correlation was found either between COX-2 and EGFR immunoreactivity.
  
  
  CONCLUSIONS
  Immunohistochemical expression of COX-2 in GBM showed large variation. Hence, determination of COX-2 expression in tumor specimen for each individual might be relevant for selection of those patients, who could benefit from adjuvant therapy with selective COX-2 inhibitors.
authors.affiliation: Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands. p.sminia@vumc.nl
authors.forename: Peter
authors.initials: P
authors.lastname: Sminia
authors.forename: T Rianne
authors.initials: TR
authors.lastname: Stoter
authors.forename: Paul
authors.initials: P
authors.lastname: van der Valk
authors.forename: Paula H M
authors.initials: PH
authors.lastname: Elkhuizen
authors.forename: Thea M
authors.initials: TM
authors.lastname: Tadema
authors.forename: Gitta K
authors.initials: GK
authors.lastname: Kuipers
authors.forename: W Peter
authors.initials: WP
authors.lastname: Vandertop
authors.forename: M Vincent M
authors.initials: MV
authors.lastname: Lafleur
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Slotman
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D001932:Brain Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D066246:ErbB Receptors / Q000096:biosynthesis*; D005909:Glioblastoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D011379:Prognosis
chemical_list: D014408:Biomarkers, Tumor; D051546:Cyclooxygenase 2; D066246:ErbB Receptors