Magnetic resonance imaging (MRI) uses powerful magnetic fields and radio waves that are fed into a computer to generate three-dimensional images of breast tissue.

MRI highlights the differences in water content and blood flow between tissues, and because tumors tend to have more blood flow than surrounding tissues, MRI is an effective tool for visualizing tumors. In some instances technicians administer contrast agents to patients in order to further improve image quality.

Breast MRI Uses

MRI does not replace mammography or ultrasound imaging of breasts. Instead it provides a powerful supplementary tool for detecting and staging breast cancer.

For example, MRI is particularly good for detecting very small tumors and therefore can be used after a suspicious spot has been detected by mammogram or ultrasound to determine whether the cancer has spread further in the breast or into the chest wall.

MRI is also especially useful for detecting tumors in women with breast implants (which can interfere with mammogram rays), and in women with dense breast tissue. This last point makes MRI a particularly desirable addition for women at high risk of developing breast cancer who are more likely to begin screening at a younger age, when breast tissue tends to be more dense.

Stanford Expertise

MRI is an exceptional tool for breast cancer diagnosis and staging, however this technology must be administered by experienced practitioners who understand its appropriate uses and its limitations.

For example, MRI does not allow the visualization of calcifications, which are sometimes the only indication of early stage breast cancer (and do show up on mammograms). Furthermore,  the placement of the MR coils relative to the tissue being imaged is critical, and accurate breast MRI requires both specialized equipment and trained imaging personnel.

World Leaders, Cross-platform Interpretation

The Stanford Cancer Center is one of the world-leaders in breast MRI. Debra M. Ikeda, Chair of Breast Imaging in the Department of Radiology, has also chaired the American College of Radiology Breast MR Imaging Lexicon Committee, a national effort to develop a MR lexicon that determines best practices and guidelines for all MR physicians and researchers.

Furthermore, the Cancer Center has brought together MRI, ultrasound, and mammogram workstations into one reading room where the results of these multiple studies can be directly correlated with each other to provide the most accurate picture of breast tumors. 

MRI-directed Biopsies

The Stanford Cancer Center is also one of the few places in the nation where physicians are experienced with special instruments that allow them to take an MRI-directed biopsy of a spot they visualize on an MRI.

Although other centers may offer breast MRI, few physicians are trained to do MRI-directed biopsies and often must take patients into surgery to get samples from tissues that may be tumors, particularly if the tumors are detected by MRI that are not visible by other methods. This can now be avoided at the Stanford Cancer Center.