The assessment of angiogenesis and fibroblastic stromagenesis in hyperplastic and pre-invasive breast lesions.

Background: To investigate the changes of the neoplastic microenvironment during the different morphological alterations of hyperplastic and pre-invasive breast lesions.

Methods: 78 in situ ductal carcinomas of all degrees of differentiation, 22 atypical ductal hyperplasias, 25 in situ lobular carcinomas, 18 atypical lobular hyperplasias, 32 ductal epithelial hyperplasias of usual type and 8 flat atypias were immunohistochemically investigated for the expression of vascular endothelial growth factor (VEGF), smooth muscle actin (SMA) and CD34, while microvessel density (MVD) was counted using the anti-CD31 antibody.

Results: VEGF expression was strongly correlated with MVD in all hyperplastic and pre-invasive breast lesions (p < 0.