A combination of digital breast tomosynthesis (DBT) and synthesized two-dimensional mammography (s2D) detects more cancers earlier with less radiation dose than DBT plus digital mammography (DM), found a study published October 25 in European Radiology.

“Results show improved diagnostic outcomes with DBT plus s2D compared to DM alone and underline the value of DBT in combination with s2D in breast cancer screening,” wrote a team led by Dr. Sylvia Heywang‑Köbrunner from the National Reference Centre Mammography Munich in Germany.

The team also highlighted the following:

• “DBT plus s2D is associated with higher CDR [cancer detection rate], lower recall rates, and a higher PPV-1 [positive predictive value for recalls] compared to DM alone in breast cancer screening.
• No differences in biopsy rates were found between screening modalities, but PPV-2 [positive predictive value for biopsies recommended] and PPV-3 [positive predictive value for biopsies performed] were higher in women screened with DBT plus s2D compared to DM alone.
• We identified inconsistent results of ICR [interval cancer rate] in two studies comparing DBT plus s2D to DM alone—resulting in no differences when pooling ICR in meta-analysis.”

DBT plus DM is seen as problematic, as both procedures expose the patient to radiation, effectively a double exposure. Synthesized 2D mammograms are calculated from the DBT datasets, saving the patient the second radiation exposure, according to the team.

“To our best knowledge, this is the first meta-analysis of biopsy rates, PPV-2, and PPV-3 in women screened with DBT plus s2D compared to DM alone. Statistically significant differences in favour of DBT plus s2D compared to DM alone were found for CDR, recall rates, PPV-1, PPV-2, and PPV-3. Biopsy rates and ICR did not differ between screening modalities,” concluded the team, which also noted that further research was needed regarding ICR stratified by age and breast density.

Sources:

Heywang-Köbrunner, S.H., Jänsch, A., Hacker, A. et al. Digital breast tomosynthesis (DBT) plus synthesised two-dimensional mammography (s2D) in breast cancer screening is associated with higher cancer detection and lower recalls compared to digital mammography (DM) alone: results of a systematic review and meta-analysis. European Radiology. https://doi.org/10.1007/s00330-021-08308-8. Available online October 25, 2021, at https://link.springer.com/article/10.1007%2Fs00330-021-08308-8. Accessed November 8, 2021.

Allegretto, Amerigo. DBT + synthesized 2D mammo detects more cancers. AuntMinnie.com. Available online October 28, 2021, at https://www.auntminnie.com/index.aspx?sec=sup&sub=wom&pag=dis&ItemID=133895. Accessed November 8, 2021.

Mokhtar, O., Abd elsalam, S., Gamal, G. et al. 3D digital breast tomosynthesis versus US in evaluating breast asymmetries. Egypt J Radiol Nucl Med 51, 110 (2020). https://doi.org/10.1186/s43055-020-00196-0. Accessed November 8, 2021.