Use of MRI to detect breast cancer rose steeply over 10 years but has now stabilized, according to a study published in JAMA Internal Medicine.
Although breast MRI is highly sensitive for breast cancer detection, its use is limited among women who are at high risk for developing breast cancer because of the test’s low specificity, its cost, and the existence of little evidence regarding mortality benefits.
Researchers from Harvard Medical School, Harvard Vanguard Medical Association, and Massachusetts General Hospital in Boston, Group Health Research Institute in Seattle, and the University of Wisconsin, undertook a retrospective cohort study to determine how breast MRIs were used in the community. They examined the records of 10,518 women, 20 years old and older, who had had at least one breast MRI between January 2000 and December 3, 2011.
The researchers established clinical indication for the examination and breast cancer risk through a prediction model based on electronic medical records from a subset of participants.
The findings showed that use of breast MRI increased more than 20 times from 6.5 per 10,000 women in 2000 to 130.7 per 10,000 in 2009, at which time the use dropped somewhat to 104.8 per 10,000 women and then stabilized.
The researchers found that screening and surveillance were rare indications for breast MRI in 2000 but accounted for 57.6 percent of examinations in 2011. A total of 30.1 percent of the women had claims-documented personal history of breast cancer and 51.7 percent a family history the disease; 3.5 percent had a documented genetic mutation.
In the subset of women with electronic records who had received screening or surveillance MRIs, only 21 percent met breast MRI criteria set by the American Cancer Society (MRI) while only 48.4 percent with documented deleterious genetic mutations were screened.
The authors concluded that breast MRI use stabilized in 2011 after sharply increasing the previous 10 years, particularly for screening and surveillance among women with a personal or family history of breast cancer. However, “most women receiving screening and surveillance breast MRIs lacked documented evidence of meeting ACS criteria, and many women with mutations were not screened,” they wrote. The authors recommended that more efforts are needed to ensure that breast MRI use and documentation are made available to women who would benefit most.