Dense breast tissue presents multiple problems for patients and physicians: The condition not only increases the risk of developing cancer, but also makes the disease more difficult to detect with traditional breast cancer screening techniques.
It remains to be seen whether emerging modalities like digital mammography and breast tomosynthesis can definitively improve cancer detection in patients with dense breasts, said lead author Elizabeth Rafferty, MD, of Massachusetts General Hospital in Boston, and co-authors of a research letter recently published online in JAMA.
“Breast density is associated with reduced mammographic sensitivity and specificity. Additionally, increased tumor size and worsened prognosis are associated with increased breast density,” they wrote. “However, which, if any, additional modalities should be recommended for women with dense breasts is not known.”
Rafferty and her team evaluated the performance of digital mammography—both with and without tomosynthesis—in assessing breast density by calculating performance metrics from 13 healthcare institutions before and after the introduction of tomosynthesis in their breast cancer screening routines.
Their results showed that in 452,320 total examinations, recall rates per 1,000 screens decreased in both dense (127 to 109) and non-dense (90 to 79) breast tissues after the addition of tomosynthesis. Cancer detection rates and positive predictive value of recalls both increased with digital mammography and tomosythesis combined.
“Addition of tomosynthesis to digital mammography for screening was associated with an increase in cancer detection rate and a reduction in recall rate for women with both dense and nondense breast tissue,” the authors concluded. “These combined gains were largest for women with heterogeneously dense breasts, potentially addressing limitations in cancer detection seen with digital mammography alone.”