Breast cancer is second to lung cancer as the leading cause of death among women in the
United States. Over 40,000 women were estimated to die of breast cancer in 2016. Early
detection is key to improved survival, and overall prognosis is directly linked to the stage
of disease at the time of diagnosis. The 5-year relative survival rate has increased since
the mid 1970's, in part owing to improvements in early breast cancer detection with screening
mammography. Screening with mammography is associated with a 16-40% relative reduction in
breast cancer mortality among women aged 40-74 years old, and mammography is the most
cost-effective method of breast cancer screening. However, cancers can be missed at
mammography, particularly in women with dense breasts. Screening with mammography alone may
be insufficient in the screening of women who are at high risk of breast cancer. The need for
more effective screening strategies to supplement mammography in these groups of women has
led to the use of dynamic contrast-enhanced (DCE) breast MRI. Of the available modalities for
evaluation of the breast, MRI has been found to have the highest sensitivity for the
detection of breast cancer, irrespective of breast density.
On the basis of evidence from nonrandomized trials and observational studies, breast MRI is
indicated as a supplement to mammography for patients at high risk with greater than 20%
relative lifetime risk. This cohort of women includes those with: a known BRCA1 or BRCA2
genetic mutation, an approximately 20-25% or greater lifetime risk of breast cancer according
to risk assessment tools, a strong family history of beast or ovarian cancer, a history of
being treated for Hodgkin's disease and certain genetic syndromes (i.e. Li-Fraumeni syndrome,
Cowden syndrome or Bannayan-Riley-Ruvalcaba syndrome). However, for women at intermediate
risk, including those with dense breast tissue, screening MRI in the United States is not
cost-effective. The cost-effectiveness of screening breast MRI depends on estimated breast
cancer incidence and examination cost. The rationale for limiting supplemental screening
breast MRI to those at greatest risk is in part due to its high cost.
Investigators have looked at ways of reducing the cost of breast MRI to improve access to it
as a supplement screening method for women who are not necessarily in the highest risk group.
One way to achieve the efficiency and rapid throughput found with screening mammography is to
shorten screening breast MRI protocols, decrease image acquisition time, and shorten image
interpretation time. Study results have suggested that shorter protocols and shorter
acquisition times can be achieved with maintenance of diagnostic accuracy comparable to that
obtained with conventional MRI protocols. Use of these abbreviated MRI protocols could result
in lower cost and faster throughput, increasing availability and providing women with dense
breasts or at intermediate risk (lifetime risk, 15-20%) greater access to breast MRI.