Angiogenesis and co-expressed of ER and c-erbB-2 (HER2/neu) protein 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. High c-erbB-2 (HER2/neu) expression has also been shown to correlate with tamoxifen resistance in patients in some studies. To investigate how tumor angiogenesis correlates with co-expression ER/c-erbB-2 (HER2/neu) 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 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. When the mean values of MVD of the various groups defined by co-expression ER/c-erbB-2 (HER2/neu) were compared, significant difference was noted (P = 1.82E-05). MVD did show a relationship with groups defined by co-expression ER/c-erbB-2 (HER2/neu) (P = 0.000422). Combining endocrine treatment with these new-targeted therapies (using antiangiogenic molecules) is a promising approach to improve present treatment strategies and overcome endocrine resistance and should be investigated in future preclinical and clinical studies.