Improvement Needed for Appropriate Use of Screening Breast MRI

Breast MRI for screening among high-risk women is increasing, but improvement is still required to ensure this imaging is used appropriately, according to a study published in JAMA Internal Medicine.

In response to a lack of data regarding national use of breast MRI in the community, researchers from Washington, New Hampshire, California, North Carolina, and Vermont, performed an observational cohort study to describe patterns of breast MRI use between 2005 and 2009.

The researchers obtained data on breast MRIs from five national Breast Cancer Surveillance Consortium registries. A total of 1,288,924 screening mammograms from women aged 18 to 79 were included. The researchers calculated the rate of breast MRI per 1,000 women within the same year and compared women who underwent MRI with women who underwent traditional mammography, looking at patient characteristics and lifetime breast cancer risk.

The results showed that the overall breast MRI use from 2005 to 2009 rose from 4.2 per 1,000 women in 2005 to 11.5 per 1,000 women in 2009. The most rapid increase occurred from 2005 to 2007, the researchers noted. The most common clinical indication was diagnostic evaluation (40.3 percent), followed by screening (31.7 percent).

Women who underwent screening breast MRI tended to be under 50 years old, white non-Hispanic, nulliparous, have a personal history of breast cancer, a family history of breast cancer, and extremely dense breast tissue compared with women who underwent screening mammography alone.

“The proportion of women screened using breast MRI at high lifetime risk for breast cancer (over 20 percent) increased during the study period from 9 percent in 2005 to 29% in 2009,” the authors wrote.

The researchers concluded that breast screening MRIs are increasing among high-risk women, but improvement is still needed to improve appropriate use among women who may benefit most from screening breast MRI.