Vascular endothelial growth factor (VEGF) in human breast cancer: correlation with disease-free survival

Studies have shown that microvessel density influences breast-cancer prognosis. Since tumor angiogenesis is considered to be substantially affected by the excretion of vascular endothelial growth factor (VEGF) from tumor cells, we examined whether VEGF concentration is different in malignant and in non-malignant breast tissue. It was also of interest to discover whether intratumoral VEGF concentration influences disease-free survival (DFS) of breast-cancer patients. Analysis is based on 120 tissue specimens taken from breast fibromas (n = 23), normal epithelial breast tissue adjacent to fibromas (n = 8) and invasive breast cancer (n = 89). VEGF concentration was quantified by using an immunoassay. Microvessel density was determined by immunostaining for factor-VIII-related antigen. Median VEGF concentration is given in pg/mg protein (25%-quantile-75%-quantile) and it was 0 (0-1.8) in normal breast tissue, 9.8 (0.52-43.0) in fibromas and 130.4 (50.8-362.2) in invasive carcinomas. A univariate Cox model revealed that node status, tumor size, estrogen-receptor concentration, histological grading and microvessel density were prognostic factors for disease-free survival in breast cancer. We found a significant correlation between VEGF concentration and microvessel count, but VEGF concentration did not significantly influence disease-free survival. Although VEGF protein was found at a significantly higher concentration in malignant than in non-malignant tissue, determination of intratumoral VEGF protein by an enzyme immunoassay was not prognostically relevant in our patient population.