Proportion of deaths according to detection mode, breast density, and tumor phenotype
| Luminal A | Luminal B | HER2 | Triple-negative | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Breast density | N Total | N Death (%) | N Total | N Death (%) | N Total | N Death (%) | N Total | N Death (%) | |
| Screen-detected cancers | <25% | 43 | 3 (7) | 30 | 0 (0)a | 4 | 0 (0) | 14 | 1 (7.1) |
| >25% | 30 | 4 (13.3) | 19 | 4 (21.1)a | 8 | 5 (62.5) | 6 | 0 (0) | |
| Interval cancers | <25% | 36 | 5 (13.9) | 16 | 4 (25) | 7 | 1 (14.3) | 15 | 3 (20) |
| >25% | 46 | 9 (19.6) | 27 | 7 (25.9) | 12 | 3 (25) | 9 | 2 (22.2) | |
| True interval cancers | <25% | 16 | 3 (18.8) | 8 | 1 (12.5) | 3 | 1 (33.3) | 8 | 3 (37.5) |
| >25% | 20 | 3 (15) | 13 | 3 (23.1) | 10 | 3 (30) | 7 | 2 (28.6) | |
↵aP < 0.05. P values were obtained using the two-sided χ2 or Fisher's exact two-sided test when appropriate, to assess the distribution of deaths among breast density categories and phenotypes within study groups.