C-ERBB-2/NEU ONCOGENE AND KI-67 ANALYSIS IN THE ASSESSMENT OF PALATAL SALIVARY-GLAND NEOPLASMS

To evaluate the role of the Ki-67 proliferation antigen and c-erbB-2/neu oncogene expression in the clinical assessment of salivary gland tumors, we followed up 71 patients with minor salivary tumors of the palate. All benign neoplasms (n = 18) showed low Ki-67 scores (<12%), whereas 26% (14 of 53) of malignant neoplasms manifested high Ki-67 scores (>12%). A significant statistical difference between Ki-67 scores for benign and malignant neoplasms was observed (p < 0.001). Ki-67 index also correlated significantly with malignant tumor grade (p = 0.04) and patient survival (p = 0.02). Only 1 of the 18 benign tumors had c-erbB-2/neu oncogene overexpression. A significant difference between c-erbB-2/neu overexpression in benign and malignant tumors was observed (p = 0.01). Overexpression of c-erbB-2/neu oncogene was noted in 38% (16 of 42) of malignant tumors and was significantly associated with aggressive tumor behavior (p < 0.001). Multivariate analysis of significant factors revealed that gender, tumor stage, and c-erbB-2/neu oncogene overexpression were jointly predictive of survival. Our data indicate that although the Ki-67 proliferating antigen and c-erbB-2/neu oncogene expression may reflect certain intrinsic biologic properties of these neoplasms, only c-erbB-2/neu overexpression is significantly associated with their biologic aggression.