Spatial Distribution of Contrast Agent and Its Correlation with MVD in Dynamic Enhanced MR for Breast Neoplasm

Objective To investigate the spatial distribution of contrast agent in dynamic enhanced MR for breast benign and malignant neoplasm, to discuss its correlation with microvessel density (MVD).Materials and Methods Both plain and dynamic contrast-enhanced MR scanning was performed in 63 patients with breast neoplasm before operation. The spatial distribution of MR contrast agent at the tumor's center and periphery and also in the space around the tumor was analyzed. The removed specimens were stained with conventional hematoxylin and eosin (HE), and stained with immunohistochemistry to estimate MVD and its spatial distribution. The relationship between the spatial distribution of MR contrast agent and MVD was analyzed. Results Significant difference in the spatial distribution of MR contrast agent existed between breast cancer and breast fibroadenoma. In breast cancer, the enhancement rate (△SI) of the early-phase signal intensity at the peripheral area was significantly higher than that at the lesion's center. In breast fibroadenoma, the ?SI of the early-phase signal intensity at the peripheral area was significantly lower than, or equal to, that at the lesion's center. The △SI at the center, peripheral area and the area around the tumor was significantly higher in cancer group than that in fibroadenoma group. Obvious positive correlation existed between the spatial distribution of contrast agent and MVD. Conclusion The spatial distribution of contrast agent in dynamic enhanced MR is extremely different between breast cancer and fibroadenoma, but it correlates well with MVD.