Assessment of Epidermal Growth Factor Receptor (EGFR) expression in human meningioma.
OBJECTIVE
This study explores whether meningioma expresses epidermal growth factor receptor (EGFR) and determines if there is a correlation between the WHO grade of this tumor and the degree of EGFR expression.


METHODS
Following institutional review board approval, 113 meningioma specimens from 89 patients were chosen. Of these, 85 were used for final analysis. After a blinded review, immunohistochemical stains for EGFR were performed. Staining intensity (SI) was scored on a scale 0-3 (from no staining to strong staining). Staining percentage of immunoreactive cells (SP) was scored 1-5 (from the least to the maximum percent of the specimen staining). Immunohistochemical score (IHS) was calculated as the product of SI and SP.


RESULTS
Eighty-five samples of meningioma were classified in accordance with World Health Organization (WHO) criteria: benign 57/85 (67%), atypical 23/85 (27%), and malignant 5/85 (6%). The majority of samples demonstrated a moderate SI for EGFR. IHS for EGFR demonstrated a significant association between SI and histopathologic subtype. Also, there was a correlation between the SP and histopathologic subtype (p = 0.029). A significant association was determined when the benign and the atypical samples were compared to the malignant with respect to the SP (p = 0.009). While there was a range of the IHS for the benign and the atypical histologic subtypes, malignant tumors exhibited the lowest score and were statistically different from the benign and the atypical specimens (p < 0.001).


CONCLUSIONS
To our knowledge, this represents the largest series of meningioma samples analyzed for EGFR expression reported in the literature. EGFR expression is greatest in benign meningiomas and may serve a potential target for therapeutic intervention with selective EGFR inhibitors.
Department of Stich Radiation Oncology, Weill Cornell School of Medicine at Cornell University, 525 East 68th Street, New York, New York 10065, USA. gaw9008@med.cornell.edu
A Gabriella
AG
Wernicke
Adam P
AP
Dicker
Michal
M
Whiton
Jana
J
Ivanidze
Terry
T
Hyslop
Elizabeth H
EH
Hammond
Arie
A
Perry
David W
DW
Andrews
Lawrence
L
Kenyon
D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D008577:Meningeal Neoplasms / Q000378:metabolism* / Q000473:pathology; D008579:Meningioma / Q000378:metabolism* / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D046888:Tissue Array Analysis
C512478:EGFR protein, human; D066246:ErbB Receptors