Introduction/BackgroundThis study estimates the percentage of detectable breast cancers in the screening population that could be found with primary and supplemental screening, and provides cost estimates for population wide supplemental screening in the U.S. Materials and MethodsPublished estimates on cancer detection rates of 2D mammography, tomosynthesis (DBT), whole breast ultrasound (US), molecular breast imaging (MBI), contrast-enhanced mammography (CEM), and MRI, the number of mammograms conducted in the United States in 2023, and the proportion of dense breast tissue, were utilized. The maximum number of detectable cancers was projected from incremental cancer detection rates of the most sensitive supplemental screening method. The proportion of cancers detectable for each modality was calculated. In 2023, Medicare reimbursement rates were used to estimate supplemental screening costs. ResultsOut of 469,437 detectable cancers, 2D mammography could detect 190,531 (41%), leaving 278,906 undetected. Adding supplemental screening could detect a combined 220,165 cancers (47%) with DBT, 237,596 (51%) with US, 331,727 (71%) with MBI, 377,049 (80%) with CEM and 469,437 (100%) with MRI. The imaging cost in US dollars to provide supplemental screening to all individuals with dense breasts in 2023 was $933M for tomosynthesis, $1.84B for US, $3.87B for CEM, $4.16B for MBI, and $6.36B for MRI. ConclusionThe study highlights potential benefits from supplemental breast cancer screening, suggesting the combination of mammography and breast MRI offers the most effective detection method though at the highest imaging cost. These findings provide valuable insights to guide future research and inform decision-making in supplemental breast cancer screening strategies.