Office of Medical Communications

Digital breast tomosynthesis (DBT) or 3D mammography was developed with the expectation it would improve detection of breast cancer in women with dense breasts and decrease false-positive results. BCSC researchers examined whether DBT would decrease the rate of interval or missed cancer and advanced cancer (either detected on the screen or within one year of a normal screen) compared to digital mammography or 2D mammography. We found that DBT did not decrease interval cancer rates in women with dense or non-dense breasts. Advanced cancer rates were decreased in a subset of women with extremely dense breasts and higher than average breast cancer risk, 3.6% of a screening population. In the nearly 44% of women in the study with non-dense breasts and low-to-average risk for breast cancer, screening by DBT resulted in fewer false-positive results and in turn fewer breast biopsies in which no cancer was detected. Among the 29% of women in the study with scattered fibroglandular densities or heterogeneously dense breasts and also a higher-than-average breast cancer risk, DBT screening had a higher rate of detection of small invasive breast cancers that were contained within the breast, suggesting that DBT may be identifying more breast cancers earlier than digital mammography. Thus, whether women undergo DBT, or digital mammography will not change the rate of a missed or advanced cancer for most women. Women with extremely dense breasts and higher than average breast cancer risk should be offered DBT to decrease their chance of being diagnosed with an advanced cancer. Women with non-dense breasts and low to average breast cancer risk that undergo DBT will experience fewer false-positive results than with digital mammography.

Kerlikowske K, Su YR, Sprague BL, Tosteson ANA, Buist DSM, Onega T, Henderson LM, Alsheik N, Bissell MCS, O'Meara ES, Lee CI, Miglioretti DL. Association of Screening With Digital Breast Tomosynthesis vs Digital Mammography With Risk of Interval Invasive and Advanced Breast Cancer. JAMA. 2022 Jun 14;327(22):2220-2230. doi: 10.1001/jama.2022.7672. PMID: 35699706. [Link]