Angiogenesis and progesterone receptor 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. Progesterone receptor is a surrogate marker for ER activity and has been used as an additional predictive factor for hormonal therapy in breast cancer. To investigate how tumor angiogenesis correlates with progesterone receptor (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 PR status were compared, significant difference was noted (P = 0.008557). 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. MVD did show a relationship with groups defined by PR status (P = 2.03076E-05). The correlation of angiogenesis with PR status may be a potential therapeutic target for the treatment and prevention of breast cancer, using antiangiogenic molecules.