There is a considerable amount of information in the news and on the Internet regarding the use of breast MRI to detect breast cancer. Also, National Mammography Day was in October, prompting many women to get their annual mammograms, and some of those women may have been further recommended to get the breast MRI (Magnetic Resonance Imaging). This is a relatively new test that is available through the Blount Memorial Breast Health Center. However, the test is expensive, and the results sometimes can be difficult to interpret. It is important to know whether the MRI findings will clarify whether cancer is present, or confuse the picture and lead to un-necessary biopsies.
The medical community still is gathering information to know which women should have this test done. There are three categories of women whom we are almost certain will benefit from this test. The first is women with a very high risk of breast cancer, usually due to a hereditary (familial) pattern of disease. If your sister, mother, mother’s sister or grandmother has had breast cancer, you may be in a high-risk group. If this is the case, regular screening with an MRI might identify small breast cancers earlier than they can be seen on a mammogram. There also is genetic testing available for women in such families to determine if they carry a high risk of developing breast cancer or passing the risk on to their daughters.
Another category of women who often benefit from MRI are those who have already been diagnosed with breast cancer. MRI sometimes can find small tumors in the same or opposite breast that are not readily apparent on a mammogram. If these tumors are biopsied and found to be cancerous, there might be a change in recommendations for treatment, especially surgical options. For example, some women who are undergoing a mastectomy might choose to have the opposite breast removed as well, if cancer is found on the other side by MRI.
Third, women diagnosed with DCIS (Ductal Carcinoma In Situ) often have mammograms that show several small speckled calcifications present throughout the breast, making it difficult to determine the true size of the tumor. MRI often can show the extent of the disease more clearly. This is important in planning surgery, knowing whether the tumor can be removed completely by local surgery (lumpectomy) or whether the entire breast must be removed in order to control the disease.
The most significant problem with breast MRI is that while it misses very few abnormalities in the breast, many of those abnormalities are not cancerous. This can be problematic, since any suspicious abnormality seen on the MRI will need to be biopsied, and often these turn out to be benign findings. Furthermore, there is no scientific evidence that for most women, finding breast cancer by MRI leads to a better outcome than finding them by mammography.
The bottom line? Ask your radiologist or a breast cancer specialist if you need an MRI, and if one is ordered for you, be sure to understand how the results will be used to make any treatment decisions.
Dr. Barry J. Roseman specializes in general surgery and surgical oncology at the Blount Memorial Cancer Center. He is board-certified by the American Board of Surgery.