US Women Travel Further for Breast MRI or Ultrasound Than Mammography, Limiting Access
A new study found the geographic distance to facilities providing breast MR or ultrasound was more than 2.7 times further than the distance to a mammography center. Given new breast density guidelines, now approximately one in two women (those who have dense breast tissue) are recommended to have supplemental breast cancer screening by breast MR or ultrasound due to their relatively higher breast cancer risk. The Harvey L. Neiman Health Policy Institute research, published in the American Journal of Preventive Medicine, measured distance to the nearest facility offering mammography, breast MR and/or breast ultrasound for 29,629 ZIP codes. The researchers compared distance between imaging types to reveal the relative extent of this barrier to access and to inform approaches to mitigate disparities.
The study found that the mean distance to a provider offering breast MR was 23.2 miles compared with 8.2 miles to a mammography provider and 22.2 miles to a breast ultrasound provider. Hence, patients on average are only about one-third as far from the nearest location offering screening mammograms than from breast MR or ultrasound, which were comparably distant. The researchers also found that the distance to access supplemental screening was not equal for all Americans.
“Differences in distance to the nearest breast imaging facilities varied by the relative socioeconomic advantage of the community as well as across the spectrum from metropolitan to small/rural areas. We found that individuals living in the most socioeconomically disadvantaged ZIP codes were further from breast imaging facilities (12.2 miles for MR, 11.5 miles for ultrasound, and 2.4 miles for mammography) compared with individuals living in the most advantaged areas” stated Eric Christensen, PhD, Research Director at the Neiman Institute. “Similar MR-mammography access patterns existed regardless of the size of the city individuals lived in. For those in metropolitan areas, breast MR was twice as far as mammography, and for those in small/rural areas, breast MR was three times as far.”
“Breast MR is now being recommended as an additional screening tool for the 50% of women with dense breasts. Having dense breast tissue is a risk factor for breast cancer and can reduce breast cancer detection by mammography alone. When breast MR is not available or contraindicated, breast ultrasound and/or contrast-enhanced mammography (CEM) can be recommended as supplemental imaging techniques as well” stated Bhavika K. Patel, MD, Vice Chair of Research at Mayo Clinic Arizona. “The results of our study indicate there either needs to be a way to reduce the differences in access to breast MR or avail all patients of effective alternatives to promote early detection and improve outcomes.”
“From an equity perspective, it is ideal to have breast MR locally accessible to all patients, but that goal is currently unrealistic due to the expense of MR equipment” stated Dr Christensen. “Given this reality, other options are needed to make supplemental screening more accessible to mitigate the negative cancer outcome disparities that can result when women do not receive recommended supplemental screening.”
“Improving access to supplemental breast cancer screening could be accomplished with CEM, which can be offered by mammography providers using the same equipment compared to the more expensive MR equipment.” stated Dr Patel. “While this approach would not solve differences in breast MR access, it has the potential to mitigate the more important outcome differences. Studies show that CEM has comparable diagnostic performance to breast MR and many trials are currently underway to assess the screening performance of CEM.”