Multiparametric MRI analysis of morphologico-functional features of DCIS - correlation with grade of nuclear atypia.

The aim was to analyze morphologico-functional characteristics of ductal carcinoma in situ (DCIS) in breast MRI to assess signs correlating with the degree of nuclear atypia. From 636 malignant lesions, 114 were DCIS (17.92%): 44 cases of high-grade (38.60%), 37 intermediate (32.45%), 33 low-grade (28.95%). MRI characteristics - T2 signal intensity (SI), shape, margins, contrast enhancement, peripheral/ductal enhancement, kinetic curve, presence of restriction of diffusion were correlated with the nuclear grade of DCIS. Statistical analysis was performed, statistical significance and Odds ratio (OR) were calculated. Signs of high-grade lesions were low SI in T2w (p=0.042), nonhomogeneous contrast enhancement (p=0.012), wash-out phenomenon (p=0.04), high SI in diffusion weighted imaging (DWI) (p<0.0001), restriction of diffusion in apparent diffusion coefficient map (p<0.0001). DWI and wash-out phenomenon reached the highest OR (56.00, 9.76). Breast MRI using DWI and multiparametric analysis provides important information about the degree of nuclear atypia.