New modalities in breast imaging: digital mammography and magnetic resonance imaging

Contrast-enhanced dynamic MR imaging parameters and histological types of invasive ductal carcinoma of breast

The diagnosis of breast cancer has progressed owing to the improvement of both MRI equipments and MR techniques. CE-MRI is expected to be more useful for diagnosis of the existence and characteristics of breast cancer than mammography and ultrasound. Forty-three breast cancer patients, who underwent breast MRI examination before surgery and had histologically confirmed invasive ductal carcinomas, were included in this study. In 19, seven and 17 of them, carcinomas were histologically classified as papillotubular, solid-tubular, and scirrhous type, respectively. In dynamic MRI studies, the MR parameters were calculated from the signal intensity determined before and at five time-points after a bolus of 0.1 mmol Gd-DTPA/kg in the chosen region of interest (ROI). The differential analysis of MR parameters with reference to histopathology was performed by one-way analysis of variance (ANOVA) in dynamic studies. Four of 15 parameters analyzed, ENH1-2, ENH1, MSLP, and SAT3, were significantly different between papillotubular and scirrhous carcinoma. The dynamic curve of papillotubular carcinoma reached a maximum in the very early phase and then decreased slowly (linear pattern), while that of scirrhous carcinoma peaked in the slightly later phase and then decreased (parabolic pattern). In the differential analysis by Kruskal-Wallis test, although no significant differences were found in any morphological parameters among three histological types, spicula formation and rim enhancement tended to appear comparatively frequently in scirrhous and solid-tubular carcinoma. CE-MRI might reveal the differences of growth characteristics among different histological types of breast carcinomas and provide a diagnostic method useful for estimation of the prognosis of breast cancer.

Multiparametric and multinuclear magnetic resonance imaging of human breast cancer: current applications

The exploration of novel imaging methods that have the potential to improve specificity for the identification of malignancy is still critically needed in breast imaging. Changes in physiologic alterations of soft tissue water associated with breast cancer can be visualized by magnetic resonance (MR) imaging. However, it is unlikely that a single MR parameter can characterize the complexity of breast tissue. Techniques such as multiparametric MR imaging, proton magnetic resonance spectroscopic (MRSI) imaging, and 23Na sodium MR imaging when used in combination provide a comprehensive data set with potentially more power to diagnose breast disease than any single measure alone. A combination of MR, MRSI, and 23Na sodium MR parameters may be examined in a single MR imaging examination, potentially resulting in improved specificity for radiologic evaluation of malignancy.