What is breast magnetic resonance imaging (MRI)?
Breast magnetic resonance imaging (MRI) uses magnetic fields to create an image of the breast.
Breast MRI is used in breast cancer screening for women at higher than average risk. It’s also sometimes used in breast cancer diagnosis and staging.
Breast MRI is not recommended in breast cancer screening for women at average risk.
Breast MRI vs. mammography
Compared to mammography, screening with breast MRI has some drawbacks [70-73]:
- Breast MRI is more invasive than mammography because a contrast agent (gadolinium) is given by vein (through an IV) before the procedure. In rare cases, women can have a reaction to gadolinium.
- Gadolinium may build up in the brain over time in people who get MRIs on a regular basis, such as women at high risk of breast cancer who get regular breast MRI screening. Whether or not this build up has health risks is under study.
- Breast MRI has more false positive results than mammography. A false positive result shows a possible breast cancer, even though breast cancer isn’t present. The suspicious area must be checked with follow-up tests, and sometimes a biopsy, to be sure there’s no breast cancer.
- Some MRI centers don’t have the special magnets needed to do an MRI of the breast or don’t have radiologists specially-trained to read breast MRIs.
- Breast MRI is expensive and isn’t always covered by insurance.
Breast cancer screening for women at higher risk
Compared to mammography alone, mammography plus breast MRI can increase detection of breast cancer in [61-64]:
Breast cancer screening recommendations
- A BRCA1 or BRCA2 inherited gene mutation
- Radiation treatment to the chest area between ages 10-30
- Li-Fraumeni, Cowden/PTEN syndrome or Bannayan-Riley-Ruvalcaba syndrome (and first-degree relatives)
- A PALB2, PTEN or TP53 inherited gene mutation
- A greater than 20 percent lifetime risk of invasive breast cancer based mainly on family history (Estimate your lifetime risk or learn more about risk.)
The NCCN encourages women with a first-degree relative with a BRCA1/2 gene mutation, but have not been tested for BRCA1/2 mutations themselves, to consider genetic testing before getting breast MRI as part of breast cancer screening .
The NCCN recommends some women talk with their health care providers about getting breast MRI as part of their breast cancer screening, including those with [3,59].
- An ATM, CDH1, CHEK2, NBN or NF1 inherited gene mutation
- Lobular carcinoma in situ (LCIS) or atypical hyperplasia
Both the NCCN and the American Cancer Society (ACS) recommend women at higher risk of breast cancer begin screening at an earlier age than women at average risk [3-4]. Figure 3.5 and Figure 3.6 outline their guidelines.
Talk with your health care provider about breast cancer screening. Together, you can make a screening plan that’s right for you.
|For a summary of research studies on breast cancer screening with breast MRI plus mammography versus mammography alone for women at higher than average risk of breast cancer, visit the Breast Cancer Research Studies section.|
Timing of breast MRI screening
- For premenopausal women, the best timing for breast MRI is days 7-15 of your menstrual cycle .
- For postmenopausal women, breast MRI can be done at any time.
- For high-risk patients getting both mammography and breast MRI every year for screening, your health care provider may stagger the tests so you get one test every 6 months.
Insurance coverage of breast MRI varies. Check with your insurance company before getting breast MRI for screening to see if it’s covered.
Women with a personal history of breast cancer
Mammography plus breast MRI is under study for screening for women with a personal history of breast cancer.
Some studies suggest, for women diagnosed with cancer in one breast, mammography plus breast MRI can find breast cancer in the opposite (contralateral) breast better than mammography alone [70-71,74].
One study found mammography plus breast MRI may also help find new cancers in the treated breast (in women who had lumpectomy) .
However, it’s still not clear whether or not breast MRI offers a screening benefit to women who have had breast cancer. So, it’s not routinely recommended.
Women with dense breast tissue
Mammography plus breast MRI is under study for screening in women with dense breast tissue [10,76-78].
Breast MRI plus mammography may find a few more breast cancers than mammography alone [10,78]. However, adding breast MRI increases false positive results and it’s unclear whether it improves breast cancer outcomes [10,78].
Both the NCCN and the ACS state there’s not enough evidence to make a recommendation for or against MRI screening for women who have dense breasts [3-4].
Learn more about breast density on a mammogram.
Learn more about breast density and breast cancer risk.