Angiogenesis and ER/PR status in primary breast cancer patients: an analysis of 158 needle core biopsies.

Formation of new blood vessels from a preexisting vascular bed (angiogenesis) is a complex multistep process, which may also permit metastasis. Estrogen and progesterone are important in breast tumorigenesis, and their effects on the breast are mediated by their respective receptors, the estrogen receptor (ER) and the progesterone receptor (PR). To investigate how tumor angiogenesis correlates with ER/PR status in breast carcinoma diagnosed on core biopsy, microvessels were counted (and graded the density of microvessels) within the initial invasive carcinomas of 158 patients. Using light microscopy, the number of microvessels was counted manually in a subjectively selected hot spot (in the most active areas of neovascularization per 400x field), and their values were separated as above or below median (low and high), without knowledge of the outcome in the patient or any other pertinent variable. When the mean values of MVD of the various groups defined by ER/PR status were compared, significant difference was noted (P = 1.57E-05). When tumors were classified as high or low MVD, based on a cut-off value (30.70175 microvessels/mm(2)), cases with high MVD were significantly more numerous in patients with ER+/PR- status. MVD did show a relationship with groups defined by ER/PR status (P = 0.000801). Assessment of tumor angiogenesis may therefore prove valuable in selecting patients with early breast carcinoma for therapeutic hormonal therapy.