Material and Method: In this study, a total of 100 invasive ductal carcinoma patients, who were diagnosed at the Department of Pathology, Ataturk University Faculty of Medicine between the years 2003-2008, were re-evaluated. Patient characteristics and clinicopathological findings were obtained from archival records. In the present study, microvessel density was determined by immunohistochemical staining by using anti-CD34 monoclonal antibody in the paraffin blocks. First, the most vascular area was selected in the tumor under a low magnification (40x) by a light microscope and then microvessels were counted under a higher magnification (200x). Patients were classified as low and high microvessel density depending on their microvessel counts. Chi-square test and multivariate linear regression analysis were used for statistical analysis (p≤0.05).

Results: We have determined that microvessel density increases as tumor size increases (p=0.001). Microvessel density was higher in patients with at least 10 lymph node metastases compared to those with no metastasis (p=0.05). However, there was no statistically significant difference between microvessel density and other prognostic factors such as histological grade, nuclear grade, patient age, vascular invasion, estrogen, progesterone receptor status, HER2/neu expression.