The Prognostic Role of Ezrin and HER2/neu Expression in Osteosarcoma

Osteosarcoma is the most common primary malignant bone tumor in Egypt. Ezrin is involved in cell adhesion to the extracellular matrix and in cell-cell interactions facilitating metastasis. HER2/neu is overexpressed in breast cancer and other types of cancer. This study aimed to assess the expression of ezrin and HER2/neu in 57 primary osteosarcoma cases and to correlate their expression with the available clinicopathologic parameters and the overall, metastasis-free and event-free survival. Both ezrin and HER2/neu were not expressed in the normal bone and they were upregulated in 82.5% and 71.9% of osteosarcoma, respectively. Positive ezrin expression was significantly associated with young age (below 25 y) (P=0.01), high grade (P=0.001), and short survival time (P=0.0001). Positive HER2/neu expression was significantly associated with high-grade osteosarcoma (P=0.04). Membranous HER2/neu expression was the only factor that showed significant impact on metastasis-free (P=0.002) and event-free survival (P=0.002). Ezrin was significantly correlated with HER2/neu expression (P=0.02). Advanced stage (P=0.0001), metastasis (P=0.0001), and recurrence (P=0.01) were the factors affecting the overall survival of osteosarcoma patients. Ezrin and HER2/neu are overexpressed and coexpressed in osteosarcoma with adverse prognostic features such as high grade. Membranous pattern of HER2/neu seems to be more important than the cytoplasmic pattern because of its impact on metastasis-free and event-free survival. Therefore, ezrin and HER2/neu could be potential prognostic markers and treatment targets for osteosarcoma.