Immunohistochemical Expression of P53 and bcl-2 in benign and malignant salivary glands tumors


Objectives: Salivary glands tumors are relatively uncommon neoplasm with widely variable histopathologic and biologic characteristics. Alteration in some proto-oncogenes and tumor suppressor genes may lead to the development and progression of these tumors. The purpose of the present study was to analyze the immunohistochemical expression of P53 and bcl-2 in some salivary gland tumors in relation to tumor size, histological grade and extent of invasion.Study Design: The series consisted of 22 formalin-fixed paraffin embedded blocks of salivary glands tumors collected from the files of Oral pathology Department./College of Dentistry/ Baghdad University. The specimens consisted of (10) benign salivary gland tumors ( Pleomorphic Adenomas) and (12) malignant salivary gland tumors [ (2) Carcinoma ex Pleomorphic Adenoma, (3) Muco-Epidermoid Carcinoma, (2) Adenocarcinoma (5) Adenoid cystic carcinoma]. These were analyzed for immunohistochemical detection of P53 and bcl-2 in their cell types.Results: Pleomorphic Adenoma showed negative expression of P53 and bcl-2 in 70% of cases, whereas all malignant salivary glands tumors were positive for P53 and bcl-2. P53 and bcl-2 immune-reactivity were associated with larger tumor size, higher tumor grade and greater extent of invasion without reaching statistical significance level.Conclusion: P53 expression could be used as a useful tumor marker for malignant transformation of Pleomorphic adenoma and bcl-2 expression could be used as a useful monitor for measuring the aggressiveness of these neoplasms.