Comparison of EGFR Expression in Ameloblastoma and Odontogenic Keratocyst

Ameloblastoma (AM) and odontogenic keratocyst (OKC) are common lesions with a high recurrence rate. Epidermal growth factor receptor (EGFR) regulates cell proliferation and survival. Considering the controversial results of previous studies regarding the expression of EGFR in odontogenic cysts, this study aimed to compare the expression of EGFR in AM and OKC.  

In this descriptive study, 49 specimens (20 AM and 26 OKC) were evaluated. Five micrometer sections were made for immunohistochemical staining. Immunohistochemical analysis was performed using super-sensitive one-step polymer-HRP. Expression of EGFR was first assessed quantitatively by measuring the count of membrane- and/or cytoplasm-stained epithelial cells in AM  (ameloblastoma-like cells, stellate reticulum, and all epithelial cell layers) and OKC (basal layer, suprabasal and basal layers, and all epithelial cell layers). Next, each specimen's mean percentage of stained cells was scored and classified into four groups (less than 5%, 5-25%, 25-50%, and more than 50% stained cells). Data were analyzed by t-test and Mann-Whitney test to compare the mean EGFR expression and the percentage of stained cells. The Chi-square test was used to compare the location of EGFR expression.

The mean percentage of EGFR expression was 81.39±10.41% in AM and 78.05±19.27% in OKC. The results showed no significant difference between AM and OKC regarding EGFR expression, EGFR score (P=0.141), or EGFR expression in different layers (P=0.303).   

EGFR expression showed no significant difference between AM and OKC.