EGFR expression in acquired middle ear cholesteatoma in children and adults.

Middle ear cholesteatomas are characterized by the presence of keratinized stratified squamous epithelium inside this cavity. It is considered to be more aggressive in childhood. In normal skin, the epidermal growth factor receptor (EGFR) is expressed in the cytoplasmic membrane of epithelial cells of the basal layer. In contrast, its expression in middle ear cholesteatoma extends to suprabasal layers. The objective of this study is to detect the presence of EGFR in cases of acquired cholesteatoma of the middle ear and correlate the expression of this receptor with patients' ages. In this cross-sectional study, cholesteatoma samples were collected from 50 patients (35 adults and 15 children) who underwent otological surgery, throughout 1 year of study. These samples were subjected to histological and immunohistochemical assays. Results were submitted to statistical analyses and main findings were: EGFR was present in the parabasal layers in 27 cases and EGFR expression was extended to all layers of the matrix in 17 cases. There were no statistically significant differences in what concerns age-related variances in EGFR expression. The intensity and location of EGFR expression in acquired cholesteatoma of the middle ear confirm the hyperproliferative capacity of keratinocytes.