Purpose
To identify breast magnetic resonance (MR) imaging biomarkers to predict histologic grade and receptor status of ductal carcinoma in situ (DCIS).
Materials and Methods
Informed consent was waived in this Health Insurance Portability and Accountability Act-compliant Institutional Review Board-approved study. Case inclusion was conducted from 7332 consecutive breast MR studies from 1/1/2009–12/31/2012. Excluding studies with benign diagnoses, studies without visible abnormal enhancement, and pathology containing invasive disease yielded 55 MR-imaged pathology-proven DCIS seen on 54 studies. Twenty-eight studies (52%) were performed at 1.5T; 26 (48%) at 3T. Regions-of-interest representing DCIS were segmented for pre-contrast, first and fourth post-contrast, and subtracted first and fourth post-contrast images on the open-source 3D Slicer software. Fifty-seven metrics of each DCIS were obtained, including distribution statistics, shape, morphology, Renyi dimensions, geometrical measure and texture, using the 3D Slicer HeterogeneityCAD module. Statistical correlation of heterogeneity metrics with DCIS grade and receptor status was performed using univariate Mann-Whitney test.
Results
Twenty-four of the 55 DCIS (44%) were high nuclear grade (HNG); 44 (80%) were estrogen receptor (ER) positive. Human epidermal growth factor receptor-2 (HER2) was amplified in 10/55 (18%), non-amplified in 34/55 (62%), unknown/equivocal in 8/55 (15%). Surface area-to-volume ratio showed significant difference (p<0.05) between HNG and non-HNG DCIS. No metric differentiated ER status (0.113