How is MRI used in the detection of breast cancer?

Answer: MRI has been used for many years to detect breast cancer. While a very sensitive tool for finding cancer, it is not accepted as a screening tool for the general population primarily because it detects a high number of benign abnormalities that mimic cancer. This can lead to a large number of additional diagnostic studies, including biopsies, for abnormalities that pose no harm to the patient. For women who are at significantly greater than normal risk for breast cancer due to family history, a gene mutation, or other risk factor, MRI is deemed an acceptable screening tool (in addition to but not in place of mammography). Even these women must weigh the benefits of MRI’s sensitivity against the high number of false positive MRI findings.

MRI can also be useful as a problem solving tool, when mammography and ultrasound don’t adequately assess a possible breast abnormality.

Some clinicians advocate the use of MRI to determine the extent of disease in patients diagnosed with breast cancer by other means. In other words, a mammogram may show one breast cancer in a patient, but the MRI may show additional sites of cancer that could change how the surgeon or oncologist treats the disease. This practice is not uniformly accepted because it hasn’t convincingly been shown to reduce breast cancer death.