From the November 2018 issue of HealthCare Business News magazine
By Dr. Nila H. Alsheik
Digital breast tomosynthesis (DBT), or 3D screening mammography, has again been solidified as the gold standard of care for breast screening according to a recent study published in Academic Radiology, and more and more facilities are offering this technology.
Despite this trend, however, utilization rates at many facilities nationwide still remain suboptimal, with only partial conversion rates to DBT. For facilities aiming for the highest patient outcomes, including reduced recall rates and optimized cancer detection rates, conversion rates over 75 percent to DBT screening confer the highest benefits.
Standardization of clinical protocols in the screening and diagnostic setting is critically important in the era of DBT. DBT confers lower recall rates and higher cancer detection rates, regardless of breast density. The data, therefore, supports uniform screening DBT utilization in all patients, and not just in those who have heterogeneously or extremely dense breast tissue. Conversely, patient care and facility performance are not optimized in hybrid screening environments where there is more than 25 percent 2D screening utilization.
To compare outcomes associated with breast cancer screening with 2D mammography alone versus in combination with DBT, researchers analyzed patient-level demographics, calculated risk levels, and clinical outcomes of more than 190,000 DBT exams and more than 130,000 DM/2D screening examinations over a two-year period at 39 imaging facilities across two healthcare systems. The study, which utilized multiple benchmarks including cancer and invasive cancer detection rates, specificity, tumor grade, size and stage of tumor at diagnosis and nodal status, demonstrated that DBT conferred a 22 percent higher cancer detection rate, as well as a sustained decrease in recall rates across the entire cohort, compared to 2D alone.
The implications of the study are far-reaching, as recalls due to false positives have been shown to create anxiety and reduce patient compliance with future screening mammography. As such, heightened sensitivity and specificity in mammography not only affects the rate of cancer detection, but potentially reduces morbidity and cost arising from unnecessary downstream procedures and imaging. In addition to being more effective than 2D alone, DBT recall rates were also lower at sites that predominantly performed DBT screening (8.02 percent), compared to facilities that perform a mix of 2D alone and DBT screening (10.43 percent).