Magnetic resonance imaging of breast lesions--a pathologic correlation.
ABSTRACT Magnetic resonance imaging of the breast is useful in assessing breast lesions. An understanding of the pathologic characteristics of the tumors may help to understand these magnetic resonance imaging observations.Large lesional size (>10 mm), ill-defined margin, and irregular outlines are associated with malignancy. These correlate with the pathological features of breast tumor, characterized by rapid growth rate, large size, and infiltrative growth pattern, invasion into stroma resulting in desmoplasia, and hence irregular outline and margin. The detection and estimation of tumor extent of invasive lobular carcinoma is problematic, even with magnetic resonance imaging, which is considered the most sensitivity. This inaccuracy likely derives from the characteristic linear, single cells infiltration growth pattern of the tumor, which is also often underestimated by clinical examination. Estimation of tumor extent after neoadjuvant chemotherapy is also essential but problematic by imaging, as the shrunken tumor becomes fibrotic, with stromal hyalinization, diminished microvasculature and tumor break up causing size underestimation. Non-enhancement of breast tumors occurs in about 8% of cases correlates with diffuse growth pattern, particularly of infiltrative lobular carcinoma. The observation of disproportionately high non-enhancing ductal carcinoma in situ remains an enigma. Finally, early rim enhancement correlates with small cancer nests, low ratio of peripheral to central fibrosis and high ratio of peripheral to central microvessel density. These may be related to increased vascular endothelial growth factor mediated increased microvessel density as well as increased permeability, which manifest as increased rapid contrast uptake and dissipation.
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ABSTRACT: To evaluate a single-pass fast spoiled gradient echo (FSPGR) two-point Dixon sequence and a gradient echo sequence with spectral fat suppression in their performance at 3 T for fat suppressed contrast-enhanced bilateral breast imaging. Twenty patients were prospectively enrolled in an imaging protocol that included axial Dixon and 3D FSPGR with spectrally selective fat saturation sequences as part of patient care in this study. Qualitative analysis was performed retrospectively by two readers who scored the images for homogeneity and degree of fat saturation, severity of artifacts, and quality of normal anatomical structures. Enhancing lesions were scored according to the confidence with which American College of Radiology (ACR) BI-RADS magnetic resonance imaging (MRI) features were identified. The Dixon sequence showed superior fat saturation homogeneity, quality of posterior anatomical structures, and decreased artifact severity that were statistically significant (P < 0.0001). The degree of fat saturation was scored higher in the Dixon sequence, although the difference did not reach statistical significance. There were no significant differences between the 3D T1-weighted FSPGR and Dixon groups for assessing lesion features. Our findings suggest that the Dixon technique is an effective fat suppression method for contrast-enhanced breast MRI. The Dixon technique also seemed to provide better anatomical definition of posterior structures and improvement in severity of artifacts.Journal of Magnetic Resonance Imaging 07/2011; 34(4):842-51. · 2.57 Impact Factor
- 03/2012; , ISBN: 978-953-51-0284-7
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ABSTRACT: To compare the accuracy of different MR sequences to measure tumor size. Eighty-six women (mean age: 53 years (30-78)) who underwent preoperative MRI for breast cancer were included. Maximal diameters of the index tumor (IT) and of the whole extent of the tumor (WET) were measured on T2-weighted (T2W) sequences, on dynamic contrast-enhanced (DCE) T1-weighted (T1W) sequences and on Maximal Intensity Projection (MIP) reconstructions. Agreements with pathological size were evaluated using concordance correlation coefficient (k). Median pathological size of IT was 20mm (13-25mm, interquartile range). Median pathological size of the WET was 29mm (16-50mm, interquartile range). Measurement of IT showed a good concordance with pathological size, with best results using T2W (k=0.690) compared to MIP (k=0.667), early-subtracted DCE frame (k=0.630) and early-native DCE frame (k=0.588). IT was visible on T2W in 83.7% and accurately measured within 5mm in 69.9%. Measurement of WET was superior using early-subtracted DCE frame (k=0.642) compared to late-native frame (k=0.635), early-native frame (k=0.631), late-subtracted frame (k=0.620) and MIP (k=0.565). However, even using early-subtracted frame, WET was accurately measured within 5mm only 39.3%. If visible, IT size is best measured on T2W with a good accuracy (69%) whereas WET is best estimated on early-subtracted DCE frame. However, when adjacent additional sites exist around IT, suspected surrounding disease components need to be proved by pathological analysis.European journal of radiology 08/2013; · 2.65 Impact Factor