Expression of epidermal growth factor receptor, transforming growth factor-alpha and Ki-67 in relationship to malignant transformation of pleomorphic adenoma.

CONCLUSION: Quantitative assessment is more sensitive as a measure of cellular protein content as compared with standard optical density measurements. The data support the hypothesis that increased epidermal growth factor receptor (EGFR) and transforming growth factor (TGF)-alpha expression is associated with early events in malignant transformation of pleomorphic adenoma (PA).

OBJECTIVE: In the present study, we attempted to identify EGFR and TGF-alpha expression and Ki-67 index in carcinoma ex-pleomorphic adenoma (Ca ex-PA) and PA. We also compared the presence of EGFR and TGF-alpha and Ki-67 index with clinical data.

MATERIALS AND METHODS: The tissues were stained with monoclonal antibodies to EGFR, TGF-alpha and Ki-67. The results were analysed using quantitative immunohistochemical analysis. We also analysed the association of patients' prognosis with clinical parameters and the histological classification of the carcinomatous component.

RESULTS: As regards the association of patients' prognosis with EGFR staining and Ki-67 index, a significant increase was observed in patients who died or had residual disease compared with patients who were alive without disease. In the immunohistochemical analysis of EGFR and TGF-alpha and Ki67 index, a significant increase was observed in Ca ex-PA, especially with adenocarcinoma, compared with PA and sialadenitis.