Association between BRCA Mutation Status, Pathological Findings, and Magnetic Resonance Imaging Features in Patients with Breast Cancer at Risk for the Mutation

PURPOSE We investigated the relationship between BRCA mutations, pathological findings, and magnetic resonance imaging (MRI) features in patients with breast cancer at risk for the mutation. METHODS Genetic testing for BRCA mutations was performed in 275 breast cancer patients with at least one risk factor for the mutation. Using the breast imaging reporting and data system MR lexicon, morphological and kinetic features were reviewed on MRI scans of 230 tumors in 209 patients. The relationship between BRCA mutations, pathologic findings, and MRI data was examined, and disease recurrence was estimated. RESULTS BRCA mutations were detected in 48 patients (23.0%), of which 21 (10.0%) were in BRCA1, and 25 (12.0%) in BRCA2. Additionally, two patients (1.0%) had mutations in both genes. Cancers in patients with BRCA1 mutations more frequently showed a higher nuclear grade (p=0.0041), and triple-negative (TN) phenotype (p<0.0001). On MRI scans, the cancers were seen as mass-type in 182 out of 230 lesions (79.1%), and nonmass type in 48 cases (20.9%). Among the features indentified by MRI, rim enhancement was significantly associated with molecular subtypes based on immunohistochemistry (p<0.0001), and nuclear grade (p=0.0387) in multiple logistic regression analysis. Rim enhancement on MRI, along with advanced pathologic N stage, was associated with increased disease recurrence (p=0.0023) based on multivariate analysis. However, the proportion of mass and nonmass tumors, and the distribution of morphological shape, margin, internal enhancement, and kinetic features assessed by MRI were not different according to BRCA mutation status. CONCLUSION BRCA1 mutations were associated with aggressive pathological characteristics, and the TN phenotype. Rim enhancement was frequently seen on MRI scans of high-grade cancers and in the TN phenotype. And it was a significant predictor of disease recurrence. However, a direct association with BRCA mutations was not observed.