Tumor angiogenesis in node-negative breast cancer: relationship with relapse free survival

There is growing evidence that angiogenesis plays an important role in the biologic aggressiveness of breast cancer. using immunohistochemical methods, several studies have shown a worse prognosis for those patients with tumors with high angiogenic activity. The aim of this study was to correlate the microvessel density with relapses in node-negative breast cancer patients who exhibited homogeneous pathologic features. The study was based on 52 women with primary invasive ductal carcinoma graded according to Bloom and Richardson classification as group II. All patients were node-negative and had a tumor 1-3 cm in diameter. Twenty six patients had a 10 year relapse free survival while the other group of 26 patients showed tumor recurrences in the same time interval. Microvessels were highlighted immunohistochemically using an antibody for Factor VIII which is an endothelial marker. Vascular density was quantified at the richest in vessels part of the tumor through an ocular eyepiece equipped with a grid with 100 subdivisions at a 400 x magnification. The vascular density counts ranged from 16 to 230 per grid field. For the relapse-free group the mean value was 35 whereas for the group with recurrences, the mean value of vessel density was 68. This difference proved to be statistically significant, and suggests that angiogenesis is closely associated with early relapse in primary breast cancer. Such results are found in the majority of the retrospective studies and show that angiogenesis is an important new prognostic indicator in early-stage breast carcinoma. This marker should be further evaluated in order to demonstrate whether adjuvant therapies with angiogenesis inhibitors could improve the prognosis of those patients at high risk, e.g., those with highly vascularized tumors.