Signal Enchancement Ratios (SERS) in Breast Carcinomas Measured by 3D Contrast-MRI and Verified by Histopathology

The goal of this study is the evaluation of a three-point contrast-enhanced magnetic resonance imaging MRI technique for characterizing breast carcinoma. We have developed a high resolution method that captures both anatomic heterogeneity as well as differences in contrast uptake pattern, using the signal enhancement ratio SER. Over 400 patients with confirmed or suspected breast cancer have been evaluated using this technique. In an initial comparison of MRI to mammography for defining the extent of disease in the breast, we reported superior capability of MRI relative to mammography, with particular value in cases of multifocal disease or presence of an associated in-situ component. We found a significant correlation between peak SER value and both tumor grade and microvessel density, and demonstrated improved diagnostic specificity of the three-point SER method over a standard two-point static method. We also evaluated the influence of time interval between surgical excision and subsequent MRI in cases of incomplete tumor resection, on the ability to diagnose residual disease. This evaluation led to a recommendation for a 28-day delay to maximize diagnostic accuracy while minimizing delay to re-excision. The characterization studies have led to the application of contrast-MRI to evaluation of treatment response for patients with locally-advanced breast cancer who undergo pre-operative chemotherapy. Our early results suggest that MRI is more accurate than conventional methods mammography and physical exam for measuring change with treatment and may provide unique non-invasive markers that can be used to predict response and recurrence.