Correlation of Contrast-Enhanced MR Findings and Tumor Microvessel Density of Breast Masses

Abstract

Purpose: To compare the contrast-enhanced dynamic MR findings of solid breast masses with their histopathologic tumor angiogenesis. Materials and Methods: Thirty-two cases of pathologically proved breast lesions (8 benign and 24 malignant lesions) examined with contrast-enhanced MRI were retrospectively reviewed, focusing on the tumor size, the maximum amount of contrast enhancement (% Signal Intensity Change, SIC), the time to peak (early or late peak) and the type of time-signal intensity curve (TSC). We compared the characteristic MR findings of breast cancer with the microscopic maximum microvessel density (MVD). Results: Among the total of 11 small lesions ( 2 cm, 9 malignant and 2 benign), 8 cases of malignant lesions showed high MVD ( 20). On the other hand, among the 21 large lesions (> 2 cm, 15 malignant and 6 benign), only two cases of malignant and five cases of benign lesions showed high MVD. More than 100% SIC was observed in a total of 11 malignant and two benign lesions, but 8 of these 11 malignant lesions showed low MVD ( 3 min) was observed in 18 (17 malignant and 1 benign) lesions, and 11 of these 17 malignant lesions showed low MVD. An early high peak and early or slow wash-out pattern, which is typical of the malignant type, was seen in 18 (17 malignant and 1 benign) lesions, but 12 of these 17 malignant lesions showed low MVD. There is no statistically significant correlation between the characteristic MR findings of breast cancer and the MVD. Conclusion: Although high MVD indicated malignancy in the case of the small lesions, the histopathologic MVD was not significantly correlated with either the increased amount of enhancement, early time-to peak or the malignant pattern of the TSC.