MRI Findings And Heterogeneity Of Triple Negative Breast Cancer

Part oneMR imaging of triple negative breast cancer with histological type: Invasive ductal carcinoma not otherwise specifiedPurpose:To retrospectively evaluate the magnetic resonance (MR) imaging findings of triple negative breast cancer (i.e. estrogen receptor [ER] negative, progesterone receptor [PR] negative, and human epidermal growth factor receptor2[HER2] negative) with histological type-invasive ductal carcinoma not otherwise specified (IDC NOS) and to compare them with non-triple negative breast cancer.Materials and Methods:From January2011to December2012, we studied78patients with immunohistochemically confirmed triple negative breast cancer who underwent breast MRI. We randomly included156patients with non-triple negative breast cancer. All the234patients were invasive ductal carcinoma not otherwise specified (IDC NOS). We evaluated the clinical and pathologic characteristics, the MRI morphologic by Breast Imaging Reporting and Data System (BI-RADS) that included tumor shape (round, oval, lobulated, or irregular), margin (smooth, irregular, or spiculated), internal enhancement (homogeneous, heterogeneous or rim enhancement), size, as well as signal intensity (low/equal, high or bright high) on T2-weighted MR images.Results:Compare with non-triple negative breast caner, mass lesion type (P=0.035), smooth mass margin (P<0.001), rim enhancement (P<0.001), and very high intratumoral signal intensity on T2-weighted MR images (P<0.001) were significantly associated with triple-negative breast cancer. Longitudinal transverse mass margin and internal enhancement into the regression model, OR value were3.279,4.577. ROC curves confirmed that mass margin combined with internal enhancement can be helpful for predicting triple negative breast cancer.Conclusion:Several MR imaging features such smooth mass margin, rim enhancement might be used for detecting triple-negative breast cancer. Part twoMR imaging of special types of Triple Negative Breast CancerPurpose:To assess MR imaging findings of special types of triple negative breast cancer and evaluate the heterogeneity of triple negative breast cancer.Materials and Methods:From January2008to December2012, we studied17patients confirmed triple negative breast cancer and with special histological type. From17special triple negative breast cancer subtypes,11cases were classified as metaplastic,4were classified as adenoid cystic,1was classified as medullary, and1was classified as secretory. We randomly included78patients with non-special triple negative breast cancer in part one. We evaluated the clinical and pathologic characteristics, the MRI morphologic that included tumor shape (round, oval, lobulated, or irregular), margin (smooth, irregular, or spiculated), internal enhancement (homogeneous, heterogeneous or rim enhancement), size, as well as signal intensity (low/equal, high or bright high) on T2-weighted MR images by univariate analyses to predict the heterogeneity of triple negative breast cancer.Results:Compared with non-special subtype of triple negative breast caner, spiculated mass margin significantly associated with special triple negative breast cancer (P=0.003)Conclusion:Special subtype triple negative cancer was prone to spiculated mass margin. Part threeSpecial types of Triple Negative Breast Cancer:correlation between MR imaging and pathologic findingsPurpose:To assess the correlation between MR imaging and pathologic findings of special types of triple negative breast cancer.Materials and Methods:From January2008to December2012, we studied17patients confirmed triple negative breast cancer and with special histological type. From17special triple negative breast cancer subtypes,11cases were classified as metaplastic,4were classified as adenoid cystic,1was classified as secretory, and1was classified as medullary. We evalued the MRI characteristic and correlated it with pathologic findings.Results:On MR imaging,11cases metaplastic carcinoma of breast often showed inrregular or spiculated margin (90.9%), heterogeneous or rim enhancement (81.8%), of which5case spindle-cell type showed bright high signal intensity on T2WI, and mixed type(4/6,66.7%) often showed high or bright high signal intensity on T2WI.4cases of adenoid cystic carcinoma showed lobulated or irregular shape.3of them exhibited high signal intensity, with photomicrographs revealing a pure (2cases) or mixed (1case) cribriform pattern with low cellularity. Only1lesion exhibited low signal intensity, and its high cellularity correlated with the solid pathological pattern. The enhancement of4cases was heterogeneous, and each case had distinctive enhancement patterns that correlated with the pathological subtype. One case of secretory carcinoma showed round shape, spiculated margin, heterogeneous enhancement, and high signal intensity on T2WI. One case of medullary carcinoma showed lobulated shape, spiculated margin, rim enhancement and slightly high signal intensity on T2WI.Conclusion:Each subtype of special triple negative breast cancer had distinctive MR imaging characteristic that correlated with the pathological subtypes.