MR imaging properties of breast cancer molecular subtypes.

ABSTRACT

OBJECTIVE: In this study, we aim at investigating the magnetic resonance (MR) imaging features of molecular subtypes, according to the BIRADS Atlas. PATIENTS AND METHODS: The preoperative MRI examinations of 104 breast cancer patients were reviewed retrospectively using the 5th Edition Breast Imaging-Reporting and Data System (BI-RADS) Atlas. According to BI-RADS, cases were classified as mass or non-mass enhancement. Background parenchymal enhancements of the cases were evaluated. The population was examined for shape, contour, enhancement characteristics of masses, distribution and internal enhancement patterns of non-mass enhancements, background parenchymal enhancement, multifocal/multicentric (MFMS) status, presence of axillary LAP, ADC values, and kinetic aspects. The Kruskal-Wallis and Chi-square tests were used to explore the connection between molecular subtypes and MR data. RESULTS: The link between molecular subtypes and mass/non-mass enhancement was discovered to be statistically significant (p=0.007). The shape (p=0.001) and contour (p=0.001) properties of the masses were observed to differ depending on the molecular subtypes. The Luminal types were usually irregularly shaped with irregular/spiculated contours, whereas the HER-2 (+) and Triple (-) subtypes were mostly oval/round with smooth contours. The subtype with the highest non-mass enhancement rate (70%) was HER-2 (+). Axillary lymphadenopathy was most common (64.3%) in the Triple (-) subtype (p=0.033). CONCLUSIONS: According to the BIRADS Atlas, molecular subtypes exhibit a wide range of imaging properties in MR in our study.