Vascular endothelial growth factor immunoexpression is increased in malignant salivary gland tumors

Abstract

OBJECTIVE : To investigate the immunoexpression of vascular endothelial growth factor (VEGF) in benign and malignant salivary gland tumors (SGT), determining its clinical and prognostic significance. MATERIAL AND METHODS : A total of 132 formalin-fixed, paraffin-embedded SGTs were organized in tissue microarray blocks and submitted to immunohistochemistry against VEGF protein. Slides were scanned and immunoreactions analyzed using Pixelcount V9 digital algorithm. Clinical and follow-up data were retrieved from patients’ medical charts. RESULTS : Tumors included 50 cases of pleomorphic adenoma, 32 mucoepidermoid carcinomas, 30 adenocarcinomas not otherwise specified and 20 adenoid cystic carcinomas. A slight male preponderance was found (M:F ratio 1.1:1.0), with a mean age of 47.5 years. Parotid gland was the most affected location. VEGF expression was found in the cytoplasm of all cases analyzed with variable intensity, proving to be overexpressed in malignant tumors if compared to pleomorphic adenoma. A significant correlation of VEGF reactivity was found only with age, showing no further significant associations. Age and presence of paresthesia were the only features that predicted an inferior specific survival rate under uni and multivariate analyses. Log-rank test evidenced VEGF high expression as a potential determinant of inferior survival, although a statistical significance could not be reached. CONCLUSION : Considering VEGF overexpression in malignant tumors and its potential association with an inferior survival rate, it can be speculated that this protein might be associated with SGTs pathogenesis and aggressiveness.