Breast MRI is recommended for screening women who are at high risk for breast cancer, usually due to a strong family history and/or a mutation in genes such as BRCA1 or BRCA2. Individuals that are considered high-risk, should have breast MRI in addition to annual mammograms.
Studies have shown that breast MRI screening can detect small cancers sometimes missed by clinical breast exams and mammography. Breast MRI is not a perfect tool. Although it is generally considered more sensitive for picking up breast cancer than mammography, it also can miss some cancers that would be detected by mammography. For example, MRI cannot detect tiny calcium deposits that can sometimes indicate early breast cancer. These are only seen on a mammogram.
For this reason, breast MRI is recommended only as a supplement to regular breast health care – annual exam by primary care provider, monthly self-exam, and regular mammogram. It is not a replacement or alternative to mammography.
Who should have breast MRI screening?
Women at high risk develop breast cancer at an earlier age and their breast cancers tend to be more aggressive than breast cancers diagnosed in women of average risk.
The American Cancer Society (ACS) recommends that all high-risk women — those with a greater than 20% lifetime risk of breast cancer — have a breast MRI and a mammogram every year. For most women, these combined screenings should start at age 30 and continue as long as the woman is in good health. According to ACS guidelines, high-risk women include those who:
- Have a known BRCA1 or BRCA2 gene mutation.
- Have a first-degree relative (mother, father, brother, sister, or child) with a BRCA1 or BRCA2 gene mutation and have not had genetic testing themselves.
- Find out they have a lifetime risk of breast cancer of 20% or greater, according to risk assessment tools that are based mainly on family history.
- Had radiation therapy to the chest for another type of cancer, such as Hodgkin’s disease, when they were between the ages of 10 and 30 years.
- Have a genetic disease such as Li-Fraumeni syndrome, Cowden syndrome, or Bannayan-Riley-Ruvalcaba syndrome, or have one of these syndromes in first-degree relatives.
The American Cancer Society also recommends that women at moderately increased risk of breast cancer — those with a 15-20% lifetime risk — consider the possibility of adding breast MRI screening to their yearly mammogram. According to ACS guidelines, this includes women who:
- Find out they have a lifetime risk of breast cancer of 15-20%, according to risk assessment tools based mainly on family history.
- Have a personal history of breast cancer, ductal carcinoma in situ (DCIS), lobular carcinoma in situ (LCIS), or abnormal breast cell changes such as atypical ductal hyperplasia or atypical lobular hyperplasia.
- Have extremely dense breasts or unevenly dense breasts when viewed by mammograms.
Other common uses for Breast MRI
- Further evaluation of abnormalities detected by mammography.
- Examination for cancer in women who have implants or scar tissue that might produce an inaccurate result from a mammogram. This test can also be helpful for women with lumpectomy scars to check for any changes.
- Detecting small abnormalities not seen with mammography or ultrasound (for example, MRI has been useful for women who have breast cancer cells present in an underarm lymph node, but do not have a lump that can be felt or can be viewed on diagnostic studies).
- Assess for leakage, collapse, or other problems associated with silicone gel or saline implants.
- Evaluate the size and precise location of breast cancer lesions, including the possibility that more than one area of the breast may be involved (this is helpful for cancers that spread and involve more than one area).
- Detecting changes in the other breast that has not been newly diagnosed with breast cancer (There is an approximately 10 percent chance that women with breast cancer will develop cancer in the opposite breast. A recent study indicates that breast MRI can detect cancer in the opposite breast that may be missed at the time of the first breast cancer diagnosis.).
- Detection of the spread of breast cancer into the chest wall, which may change treatment options.
- Determining whether lumpectomy or mastectomy would be more effective.
- Detection of breast cancer recurrence or residual tumor after lumpectomy
- Evaluation of a newly inverted nipple change