MRIs used to detect breast cancer
David A. Russell, MD, is a radiologist certified in breast imaging at Banner Gateway Medical Center’s Women’s Imaging Center in Gilbert.
Question: I have heard that MRI is now used for detecting breast cancer. When is it appropriate for women to have a breast MRI instead or in addition to a mammogram?
Answer: Magnetic Resonance Imaging (MRI) of the breast is a relatively new, but very important tool in the diagnosis and treatment of breast cancer. The value of MRI depends on its appropriate use based on recognized indications and on the expertise of the radiologist performing and interpreting the study.
Mammography has been proven to detect cancer at an early stage and, with appropriate treatment, to reduce mortality from breast cancer. For a subset of women at high risk of breast cancer, breast MRI may contribute to earlier detection of cancer.
The current indications for annual breast MRI as a screening examination include patients with mutation of the BRCA genes; a history of a first degree relative as a carrier of the BRCA gene; radiation therapy to the chest between ages 10 and 30; a lifetime risk of breast cancer of 20% or greater based on a multiple risk factor assessment conducted by a physician; and certain unusual genetic syndromes.
Other more common indications for breast MRI include a personal history of breast cancer, where MRI can be useful in detecting up to 20% of additional hidden cancers. Women with very dense breasts and patterns difficult to evaluate with mammography or ultrasound are also good candidates. It is also used in treatment planning for patients with a new diagnosis of breast cancer, and is the gold standard for evaluating breast implants and for differentiating scar tissue from recurrent or residual breast cancer.
Breast MRI does not replace mammography as the primary screening examination for breast cancer, and it is not indicated for all patients. However, radiologists involved in the diagnosis of breast cancer rely heavily on this tool when appropriate.