Two Different Types of Ring-Like Enhancement on Dynamic MR Imaging in Breast Cancer: Correlation With the Histopathologic Findings

Purpose: To describe two different types of "ring-like enhancement" seen on dynamic magnetic resonance imaging (MRI) of breast cancer, and compare their histopathological features. Materials and Methods: A total of 326 breast carcinomas in 311 patients were evaluated regarding the existence and appearance of "ring-like enhancement" in comparison to other MR imaging and histopathological findings. Results: Early peripheral enhancement (EPE) was observed in 81 of 326 lesions (24.8%) and delayed rim enhancement (DRE) in 110 (33.7%). Spiculated mass, invasive ductal carcinoma with abundant stroma, central fibrosis/necrosis, and a higher degree of fat invasion correlated with EPE (P < 0.001.). DRE correlated with lobulated or round mass with a smooth border, invasive ductal carcinoma with scanty stroma, higher degrees of inflammatory change and surrounding compressed tissue, and less fat invasion (P <0.001). EPE correlated with the ratio of the peripheral to central blood vessel density (P = 0.0036) and DRE with the ratio of the peritumoral to peripheral lymph vessel density (P = 0.0298). Conclusion: The appearance of two different types of ring-like enhancement on dynamic MRI in breast cancers was affected by the morphologic features, various histological factors reflecting the growth pattern of the mass, and angiogenesis and lymphangiogenesis.