Lilian Wang MD, Presenter: Nothing to Disclose

Julia Rose Robinson MD, Abstract Co-Author: Nothing to Disclose

Cynthia Kay Brooks MD, Abstract Co-Author: Nothing to Disclose

Kathleen A. Meyer MD, Abstract Co-Author: Nothing to Disclose

Hongyan Du MS, Abstract Co-Author: Nothing to Disclose

Paula M. Grabler MD, Abstract Co-Author: Nothing to Disclose

Preoperative breast MRI is used to evaluate for extent of disease in women with newly diagnosed breast cancer. Published trials report occult contralateral malignancies in 3-5% of women undergoing breast MRI. Research on the utility of MRI has included all patients with recently diagnosed breast cancer, regardless of mode of detection and presentation at diagnosis. The purpose of this study is to evaluate the utility of breast MRI in patients with screen-detected breast cancers, and to determine whether patients with early screen-detected cancers benefit from MRI as compared to all patients with recently diagnosed breast cancer and to patients who do not undergo MRI.

Under IRB approval, a retrospective review of all screen-detected cancers between 2007-2010 was performed. Patients were divided into those with and without breast MRI. Patient demographics, breast density, screening interval, index histology, lesion size, and lymph node positivity were analyzed for the two groups. The rate of positive surgical margins was compared between the two groups. Of patients who underwent MRI, the number of additional biopsies performed, rate of change in surgical management, and rate of contralateral malignancy were evaluated.

Of 411 patients with screen-detected cancers, 269 patients underwent pre-operative MRI, compared to 142 patients without MRI. Higher breast density was noted in the MRI group compared to the no MRI group. Patient demographics, screening interval, index histology, lesion size, and lymph node positivity were not significantly different between the two groups. There was no significant difference in positive margin status between the MRI group and no MRI group (11.9% vs. 14.1%). In the MRI group, additional biopsies were performed in 35.7% patients, with a PPV of 28.9%. Contralateral malignancy was identified in 3.0% of patients and ipsilateral malignancy in 12.0% of patients. Overall, a change in management occurred in 18.6% of patients undergoing MRI. 

Patients with screen-detected cancers receive similar benefit from pre-operative breast MRI as compared to all patients undergoing breast MRI for extent of disease, with a contralateral malignancy rate of 3.0%, which is within the range published within the literature.  

Breast MRI is useful in the pre-operative evaluation of breast cancer patients, regardless of mode of detection or presentation at diagnosis.

Wang, L, Robinson, J, Brooks, C, Meyer, K, Du, H, Grabler, P, Utility of Preoperative Breast MRI in Patients with Screen-Detected Breast Cancer.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12025204.html