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

Salivary gland tumors (SGTs) consist of a heterogeneous group of lesions accounting for 3% to 10% of all head and neck neoplasms. Little is known about their angiogenic properties, and despite vascular endothelial growth factor (VEGF) has been previously studied in these lesions, further investigations are warranted to better determine its clinical and prognostic significance. In the current study, 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 algorithm (Aperio Technologies Inc, Vista, CA, USA). Clinical and follow-up data were retrieved from patients' medical charts. 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 (1.1:1.0), with a mean age of 47.5 years. Parotid gland was the most affected location. Vascular endothelial growth factor expression was found in the cytoplasm of all cases analyzed with variable intensity, proving to be overexpressed in malignant tumors if compared with 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 a lower specific survival rate under univariate and multivariate analyses. Log-rank test evidenced VEGF high expression as a potential determinant of reduced survival, although a statistical significance could not be reached. Hence, considering VEGF overexpression in malignant tumors and its potential association with a lower survival rate, this protein might be associated with SGTs pathogenesis and aggressiveness.