MR imaging of the breast tumor with special emphasis on tumor vascular characterization for tumor enhancement

The purpose of this study was to reveal the differences of the 2 D and 3 D tumor microvessel status between breast carcinomas and breast benign lesions, which show rapid strong enhancement by dynamic MR imaging. Total 20 breast lesions including 14 invasive ductal carcinomas, 1 intraductal carcinoma and 5 benign lesions underwent dynamic MR imaging and the vascular density of above lesions were quantitatively analyzed by 2 D computer-assisted vascular imaging system. Individual early enhancement rate was compared with each vascular density statistically. In 2 D image analysis, linear correlation was obtained only between rapid enhancement rates and capillary densities of benign lesions. For 3 D imaging of tumor microvessel characteristics, 3 D reconstructed images by confocal laser scanning microscopy were employed in another 5 invasive ductal carcinomas using FITC-conjugated gelatin infusion technique. In 3 D image analysis, morphological abnormality including torturous branching and focal segmentation patterns of microvessels were seen in breast carcinomas, furthermore, physiologically hyperpermeable microvessels which never identified in normal parenchyma were frequently observed. From this quantitative 2 D and qualitative 3 D image analysis of tumor microvessels, dynamic MRI was strongly influenced by morphological and physiological characteristics of tumor microvessels, therefore the radiological depiction of tumor microvessel characteristics may lead to improve the diagnostic accuracy of MR imaging for breast carcinoma. (author)