Magnetic resonance imaging findings of non-mass enhancements in the breast and their association with malignancy.

Our aim is to investigate the relationship between the MRI (Magnetic Resonance Imaging) features of non-mass enhancement (NME) lesions and malignancy. MRI findings of 200 and 2 NME lesions were retrospectively evaluated. Age, family history of breast cancer, lesion pathology results, and follow-up durations of the patients were obtained from medical records. Based on follow-up findings and pathology results, the lesions were classified into 3 groups as benign, high-risk, and malignant. The association between these groups and MRI features was analyzed statistically. Segmental (48.4%) and diffuse (85.7%) distribution patterns, as well as clumped (51.5%) and clustered ring (100%) enhancement patterns of NME lesions, were found to be associated with malignant lesions. According to the time-intensity curve, a Type 3 curve was associated with malignant lesions in 84.6% of cases. When evaluating the number of dynamic curves, lesions with multiple curves were considered malignant in 29.2% of cases. Regarding apparent diffusion coefficient (ADC) values, malignant and high-risk lesions had significantly lower ADC values compared to benign lesions. In this study, segmental and diffuse distribution patterns, clumped and clustered ring enhancement, Type 3 curve, and low ADC values were found to be associated with malignant lesions.