The Role of Breast Magnetic Resonance Imaging in the Diagnosis of Ductal Carcinoma In Situ

Ductal carcinoma in situ (DCIS), the noninvasive breast malignant tumor originates from the terminal ductal-lobular units (TDLU). The typical feature of DCSI is the formation of calcifications. Up to 90% of DOS are diagnosed on mammographic examinations, as clinically asymptomatic. Between 10% and 20% of DCIS remain mammographically occult due to the lack of calcifications and/or small tumor dimensions. Contrast-enhanced breast magnetic resonance imaging (MRI) detects mammographically occult breast lesions, thus defining morphologic features of the lesion and the dynamics of signal intensity changes due to contrast enhancement. Distribution of contrast enhancement signal intensity increase in DCIS most frequently includes segmental, ductal and linear patterns, followed by regional enhancement pattern, while the intralesional contrast uptake most frequently includes the nodular pattern with the areas of confluence. Post-contrast signal intensity increase in DCIS is most frequently fast in the initial phase (wash-in), while the whole dynamic of contrast-enhancement includes either of the three possible time-intensity curve (TIC) types (persistent, plateau or washout), although the plateau TIC is considered to be more frequent. Breast MRI has high sensitivity in the diagnosis of invasive breast cancer, varying from 90% to 100%; the sensitivity in the diagnosis of DCIS is lower (77-96%). For the time being, the primary role of MRI in DCIS is planning of breast-conserving surgery (BCS) for the evaluation of lesion extension. Further development of MRI in the diagnosis of DCIS includes the implementation of the principles of functional and molecular imaging.