Digital Breast Tomosynthesis vs Digital Mammography in a Breast Cancer Screening Program


Key Points

  • Digital breast tomosynthesis, including synthetic 2D mammograms, did not perform better than standard digital mammography as a screening tool.
  • Cancer was detected by screening in 0.66% of patients in the digital tomonsynthesis group vs 0.61% in the digital mammography group.

In a Norwegian study (To-Be) reported in The Lancet Oncology, Hofvind et al found that digital breast tomosynthesis (including synthetic 2D mammograms) did not perform better than standard digital mammography in a population-based breast cancer screening program.

Study Details

BreastScreen Norway offers all women aged 50 to 69 years two-view (craniocaudal and mediolateral oblique) mammographic screening every 2 years. The study involved 28,749 eligible women attending the program in Bergen in 2016 and 2017. Patients were randomly assigned to the digital breast tomosynthesis group (n = 14,380) or the digital mammography group (n = 14,369).

The primary outcome measure was screen-detected breast cancer, stratified by screening technique.  

Screen-Detected Cancers

No difference in screen-detected breast cancers was observed between the groups. Cancers were detected by screening in 95 women (0.66%) in the digital breast tomosynthesis group vs 87 (0.61%) in the digital mammography group (risk ratio = 1.09, P = .56). Screening-detected ductal carcinoma in situ was found in 0.10% of patients screened with digital breast tomosynthesis vs 0.11% screened with digital mammography (P = .86) and invasive cancer was detected in 0.56% vs 0.49% (P = .47). 

The investigators concluded, “This study indicated that digital breast tomosynthesis, including synthetic 2D mammograms, was not significantly different from standard digital mammography as a screening tool for the detection of breast cancer in a population-based screening program. Economic analyses and follow-up studies on interval and consecutive round screen-detected breast cancers are needed to better understand the effect of digital breast tomosynthesis in population-based breast cancer screening.”

Solveig Hofvind, PhD, of the Department of Breast Screening, Cancer Registry of Norway, is the corresponding author for The Lancet Oncology article.

Disclosure: The study was funded by Cancer Registry of Norway, Department of Radiology at Haukeland University Hospital, University of Oslo, and Research Council of Norway. For full disclosures of the study authors, visit

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.