A study published in the August 2007 issue of Radiology found that magnetic resonance imaging (MRIs) caught more breast cancers in women at high risk for the disease than either mammography or ultrasound.
The study included 171 women, average age 46, who had no symptoms of breast cancer but were at high risk for the disease (women age 25 and older who carry one of the breast cancer genes, BRCA1 or BRCA2, or who have a 20% probability of carrying a mutation or a strong family history of breast and ovarian cancer). Six breast cancers were detected, all of them found by MRI while mammography found only two, and ultrasound just one.
So far, using an MRI along with mammography can be justified only in high-risk women because of the higher cost of MRIs, the risk involved in injecting contrast material needed to display very small lesions, and the incidence of false-positives that require women to undergo follow-up biopsy. Further research is needed to determine if MRIs should be added to screenings for older women or a broader group of women.