High breast tissue density increases breast cancer (BC) risk, and the risk of an interval BC in mammography screening. Density-tailored screening has mostly used adjunct imaging to screen women with dense breasts, however, the emergence of tomosynthesis (3D-mammography) provides an opportunity to steer density-tailored screening in new directions potentially obviating the need for adjunct imaging. A rapid review (a streamlined evidence synthesis) was performed to summarise data on tomosynthesis screening in women with heterogeneously dense or extremely dense breasts, with the aim of estimating incremental (additional) BC detection attributed to tomosynthesis in comparison with standard 2D-mammography. Meta-analysed data from prospective trials comparing these mammography modalities in the same women (N = 10,188) in predominantly biennial screening showed significant incremental BC detection of 3.9/1000 screens attributable to tomosynthesis (P < 0.001). Studies comparing different groups of women screened with tomosynthesis (N = 103,230) or with 2D-mammography (N = 177,814) yielded a pooled difference in BC detection of 1.4/1000 screens representing significantly higher BC detection in tomosynthesis-screened women (P < 0.001), and a pooled difference for recall of −23.3/1000 screens representing significantly lower recall in tomosynthesis-screened groups (P < 0.001), than for 2D-mammography. These estimates can inform planning of future trials of density-tailored screening and may guide discussion of screening women with dense breasts.