Expression of Epidermal Growth Factor Receptor by Odontogenic Cysts: A comparative Study of Dentigerous Cyst and Odontogenic Keratocyst

Abstract: Background and Aim: Compare with Dentigerous cyst, Odontogenic Keratocyst is one of exclusive developmental cyst with unique clinical and histopathologic features. Considering the determining role of epidermal growth factor receptor (EGFR) in cell proliferation and survival, and the controversial results of previous studies regarding the expression of this marker by the odontogenic cysts, this study aimed to compare the expression of EGFR marker by Dentigerous cyst (DC) and odontogenic Keratocyst (OKC) as two lesions with more common neoplastic transformation.   Material and methods: In this experimental study, 49 specimens (23 DCs and 26 OKCs) were evaluated. Immunohistochemical staining was performed using EGFR antibody. Evaluation of EGFR expression was made regarding to Tie-JUN Li et al. So, The location of EGFR expression in the epithelial cells ( Basal layers, Suprabasal & basal , All layeres) were assessed through histopathologic sections.. Data were analyzed using the Mann-Whitney test, t-test and chi-square test. Results: In The present Study, of 49 evaluated cases, the mean percentage of EGFR expression was 58.20±17.97% in the 23 DC and 78.05±19.27% in the 26 OKC specimens. The EGFR expression of OKC was significantly higher than DC (P=0.001). However, the Mann-Whitney test showed no significant difference regarding EGFR score (P=0.144). The chi-square test revealed no significant difference in expression of EGFR in the basal layer, basal and suprabasal layers and all layers (P=0.524). Conclusions: The expression of EGFR marker in OKC was significantly higher than in DC, which may justify the progressive growth potential of OKC.