VASCULAR ENDOTHELIAL GROWTH-FACTOR IN SQUAMOUS-CELL HEAD AND NECK-CARCINOMA - EXPRESSION AND PROGNOSTIC-SIGNIFICANCE

The growth of solid tumors is dependent on angiogenesis, the formation of new blood vessels. Vascular endothelial growth factor (VEGF) is a secreted endothelial cell-specific growth factor, which is induced by tissue hypoxia and is angiogenic in vivo, We investigated VEGF express ion in squamous cell head and neck carcinomas by immunohistochemical t echniques, All of the 156 patients studied had been treated with radic al surgery and postoperative radiotherapy and were followed up until d eath or for at least 5 years. Of the tumors examined, 31% showed cytop lasmic staining for VEGF in carcinoma cells, Some of the tumor-infiltr ating inflammatory cells, including plasma cells and tissue macrophage s, showed high levels of VEGF expression in all of the carcinomas stud ied, Staining for VEGF was also found in acinic epithelial cells of hi stologically normal salivary glands and in normal stratified squamous epithelium adjacent to tumor, No association tvas observed between the VEGF expression of carcinoma cells and histologic grade, TNM stage, t umor microvessel count, or overall survival. These results demonstrate that in squamous cell head and neck cancer, in addition to being expr essed by cancer cells VEGF is frequently expressed by tumor infiltrati ng inflammatory cells and by cells of histologically normal adjacent t issues; this suggests a possible role in tumor angiogenesis. Our resul ts also suggest that angiogenic factors other than VEGF might provide the positive regulatory signals needed for tumor angiogenesis, in squa mous cell head and neck cancer, carcinoma cell VEGF expression is not a prognostic marker.