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 more invasive than mammography because a contrast agent is given through an IV before the procedure.
At this time, breast MRI is mostly used in breast cancer diagnosis and staging. It's also used in breast cancer screening for women at higher risk.
Learn more about breast MRI and the diagnosis of breast cancer.
Breast cancer screening for women at higher risk
Compared to mammography alone, mammography plus breast MRI can increase detection of breast cancer in [54-56]:
For women at higher risk of breast cancer
The National Comprehensive Cancer Network (NCCN) recommends yearly screening with mammography plus breast MRI for some women at higher risk of breast cancer, including women with [8]:
- A BRCA1 or BRCA2 mutation
- A first-degree relative with a BRCA1/2 mutation, but personally have not been tested for BRCA1/2 mutations
- Radiation treatment to the chest area between ages 10-30
- Li-Fraumeni, Cowden/PTEN or Bannayan-Riley-Ruvalcaba syndrome (and first-degree relatives)
- An ATM, CDH1, CHEK2, NBN, NF1, PALB2, PTEN, STK11 or TP53 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.)
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 [8,12]. 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.
Women with a personal history of breast cancer
The NCCN recommends yearly breast MRI (and yearly mammography) for women with a history of breast cancer who have [67]:
- A BRCA1 or BRCA2 mutation
- Li-Freumeni syndrome or a TP53 gene mutation
- PTEN syndrome/Cowden syndrome or a PTEN gene mutation
Mammography plus breast MRI is under study for screening for other women with a 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 [64-66]. One study found mammography plus breast MRI may also help find new cancers in the treated breast (in women who had lumpectomy) [124].
However, MRI is not recommended for these women at this time.
Women with dense breast tissue
Mammography plus breast MRI is under study for screening in women with dense breast tissue [68-71].
When added to mammography, breast MRI may find a few more breast cancers than mammography alone [7]. However, adding breast MRI increases false positive results and it's unclear whether it improves breast cancer outcomes [7].
Both the NCCN and the ACS feel there's not enough evidence to make a recommendation for or against MRI screening for women who have dense breasts [8,12].
Learn more about breast density on a mammogram.
Timing of breast MRI screening
For premenopausal women, the best timing for breast MRI is day 7-15 of the menstrual cycle [8].
There is no recommended timing for breast MRI for women after menopause.
Insurance coverage
Insurance coverage of breast MRI varies.
You may wish to talk with your insurance provider before getting breast MRI screening to see if it's covered.
Breast cancer screening for women at average risk
Screening with mammography plus breast MRI is not recommended for women at average risk of breast cancer.
Screening with breast MRI has some drawbacks.
- Breast MRI is more invasive than mammography because a contrast agent is given by vein (through an IV) before the procedure. In rare cases, women can have a reaction to the contrast agent.
- Breast MRI has more false positive results than mammography.
- Some MRI centers can't do an MRI of the breast or they don't have radiologists specially-trained to read MRI images of the breast.
- Not all centers can do an MRI-guided biopsy to follow-up on an abnormal finding that can only be seen on a breast MRI (can't be seen with other imaging such as mammography).
- Breast MRI is expensive and not always covered by insurance.
Researchers are studying whether screening with breast MRI can benefit women at average risk.
Learn more about false positive results.
Learn more about breast MRI and the diagnosis of breast cancer.