Role of Breast MRI in Women with Newly Diagnosed Breast Cancer

According to guidelines published in the Journal of the National Comprehensive Cancer Network, the addition of high-quality breast magnetic resonance imaging (MRI) to other imaging techniques such as mammography can help evaluate the extent of the cancer in women with newly diagnosed breast cancer, and can also be used to screen the opposite breast for cancer.

MRI uses radio waves and a magnet to create detailed images of the inside of the body. The American Cancer Society now recommends that women at high risk of breast cancer undergo yearly breast cancer screening with breast MRI in addition to mammography. These recommendations were prompted by several studies of MRI screening of women at high risk of breast cancer. While these studies found that the addition of MRI to mammography increased the frequency of false-positive test results compared with mammography alone, it also produced important improvements in breast cancer detection.

In addition to being used to screen women for the presence of breast cancer, MRI can also be used to evaluate the extent of disease in women with newly diagnosed breast cancer. A recent publication in the Journal of the National Comprehensive Cancer Network summarized what is known about breast MRI in women with newly diagnosed breast cancer, and provided recommendations regarding the use of MRI in this setting. Some of the key points are as follows:

• When MRI is used, it should be used in addition to (not in place of) other standard approaches to imaging such as mammography and ultrasound.
• A potential benefit of MRI among women with newly diagnosed breast cancer is more accurate definition of the extent of the known cancer, as well as identification of other areas of cancer in the affected breast or the opposite breast. For example, among 3% to 5% of women with a newly diagnosed breast cancer, MRI will identify previously undetected cancer in the opposite breast.
• It’s still unclear whether use of MRI to guide treatment decisions will reduce the risk of recurrence or improve survival.
• It’s important to remember that MRI can produce false-positive results. This means that areas that are suspicious for cancer on the basis of MRI will generally need to be biopsied to confirm the presence of cancer. Centers that perform breast MRI should also be able to perform MRI-guided biopsy or needle localization.
• Proper equipment, imaging technique, and provider training are important to achieving the best results from MRI.

This review indicates that in addition to its role in the screening of women at high risk of breast cancer, MRI may also play a role in the evaluation of women with newly diagnosed breast cancer.

Reference: Lehman CD, DeMartini W, Anderson BO, Edge SB. Indications for breast MRI in the patient with newly diagnosed breast cancer. Journal of the National Comprehensive Cancer Network. 2009;7:193-201.