Factors associated with breast MRI use among women with a family history of breast cancer.

Although annual breast magnetic resonance imaging (MRI) is recommended for women at high risk for breast cancer as an adjunct to screening mammography, breast MRI use remains low. We examined factors associated with breast MRI use in a cohort of women with a family history of breast cancer but no personal cancer history. Study participants came from the Sister Study cohort, a nationwide, prospective study of women with at least 1 sister who had been diagnosed with breast cancer but who themselves had not ever had breast cancer (n = 17 894). Participants were surveyed on breast cancer beliefs, cancer worry, breast MRI use, provider communication, and genetic counseling and testing. Logistic regression was used to assess factors associated with having a breast MRI overall and for those at high risk. Breast MRI was reported by 16.1% and was more common among younger women and those with higher incomes. After adjustment for demographics, ever use of breast MRI was associated with actual and perceived risk. Odds ratios (OR) were 12.29 (95% CI, 8.85-17.06), 2.48 (95% CI, 2.27-2.71), and 2.50 (95% CI, 2.09-2.99) for positive BRCA1/2 test, lifetime breast cancer risk ≥ 20%, and being told by a health care provider of higher risk, respectively. Women who believed they had much higher risk than others or had higher level of worry were twice as likely to have had breast MRI; OR = 2.23 (95% CI, 1.82-2.75) and OR = 1.76 (95% CI, 1.52-2.04). Patterns were similar among women at high risk. Breast cancer risk, provider communication, and personal beliefs were determinants of breast MRI use. To support shared decisions about the use of breast MRI, women could benefit from improved understanding of the chances of getting breast cancer and increased quality of provider communications.