Evaluation of epidermal growth factor receptor (EGFR), proliferation (Ki-67) and apoptosis (P53) in salivary mucoepidermoid carcinoma in relation to tumor grade


Background: Mucoepidermoid carcinoma (MEC) is the most common salivary gland malignancy. Theydisplay a variety of biological behaviours, and several systems have, therefore, been proposed to gradethis neoplasm. Today, the most popular grading systems are Auclair et al, (1992) and Brandwein et al,(2001)grading systems. Assessment of cellular proliferation, apoptosis and growth molecules are important factorsin tumor kinetic which may reflect tumor biological behaviour.Materials and methods: Immunohistochemical analyses of seventeen cases of -fixed paraffin-embeddedtissue blocks of MEC of salivary gland origin using (Ki-67, P53 and EGFR) monoclonal antibodies.Results: The samples comprised of ten males and seven females to give male to female ratio (1.4:1). Themean age was (47.06±8.5) years. The submandibular salivary gland was the most predominant affected site(5 cases). 100% of cases were EGFR immunopositive. Only 47% of MEC cases showed Ki-67 immunopositivity,while P53 immunopositivity were shown in 94% of MEC cases. There was no statistically significantcorrelation regarding P53 or EGFR markers in relation with grading systems. There was a statisticallysignificant correlation between the expression of Ki-67 marker and Auclair grading system. There were nosignificant statistical correlation among markers except between Ki-67 expression and P53.Conclusions: Assessment of tumor biology in term of apoptosis (p53), proliferation (Ki-67) and EGFR are notreflected on tumor grade