Abimbola Oluwayemisi Orisamolu1, Catherine S. Klifa1, Sachiko Anne Suzuki1, Juan Nicolas Lessing2, Jessica E. Gibbs1, Dorota Jakubowski-Wisner1, Bonnie N. Joe1, Eunsil Shelley Hwang2, Nola M. Hylton1
1Radiology, University of California, San Francisco, San Francisco, CA, USA; 2Surgery, University of California, San Francisco, San Francisco, CA, USA
In this project we quantified changes in breast tissue composition following 3 months of tamoxifen therapy in 16 premenopausal patients with Ductal Carcinoma in Situ (DCIS). Contrast-enhanced MRI data were obtained before and after tamoxifen treatment, before surgery. Volumetric breast density was extracted from MRI data at all time points, and defined as the ratio of fibroglandular tissue volume over total breast volume. Results show a mean MR breast density decrease of 13.5% during the 3 months therapy, in women with mixed MR density. These results suggest that tamoxifen affects breast density even in a short duration therapy and that these effects are quantifiable using MRI.