Table 2 Cumulative risks (in %) and 95% confidence intervals (in parentheses) for contralateral breast cancer depending on age at first breast cancer observed in relatives of index patients.
| Â | BRCA1 | BRCA2 | BRCA negative |
|---|---|---|---|
Age at first breast cancer < 40 years | Â | Â | Â |
5 years after first breast cancer | 14.1 (10.1-18.0) | 2.9 (0.0-6.3) | 4.8 (2.6-6.9) |
10 years after first breast cancer | 30.1 (24.0-36.2) | 18.2 (7.9-28.5) | 10.6 (6.8-14.4) |
15 years after first breast cancer | 40.8 (33.2-48.3) | 20.9 (9.7-32.1) | 15.3 (10.4-20.3) |
25 years after first breast cancer | 55.1 (45.4-64.9) | 38.4 (18.5-58.2) | 28.4 (20.5-36.3) |
Age at first breast cancer 40-49 years | Â | Â | Â |
5 years after first breast cancer | 9.2 (5.8-12.5) | 6.9 (2.7-11.1) | 4.2 (2.9-5.5) |
10 years after first breast cancer | 16.7 (11.7-21.7) | 13.4 (7.0-19.8) | 8.4 (6.3-10.5) |
15 years after first breast cancer | 23.2 (16.9-29.6) | 22.0 (12.1-31.9) | 10.7 (8.1-13.3) |
25 years after first breast cancer | 44.5 (33.2-55.7) | 40.5 (22.4-58.6) | 18.1 (13.9-22.3) |
Age at first breast cancer ≥ 50 years |  |  |  |
5 years after first breast cancer | 7.1 (3.8-10.5) | 3.5 (0.9-6.1) | 3.6 (2.7-4.5) |
10 years after first breast cancer | 11.4 (6.5-16.3) | 10.4 (4.9-16.0) | 5.5 (4.3-6.7) |
15 years after first breast cancer | 18.7 (11.0-26.3) | 15.5 (7.8-23.3) | 8.1 (6.3-9.9) |
25 years after first breast cancer | 21.6 (12.3-30.8) | 15.5 (7.8-23.3) | 12.9 (8.9-17.0) |
Total | Â | Â | Â |
5 years after first breast cancer | 10.4 (8.3-12.5) | 4.5 (2.5-6.5) | 3.9 (3.2-4.6) |
10 years after first breast cancer | 20.4 (17.1-23.7) | 13.2 (9.2-17.2) | 7.1 (6.0-8.2) |
15 years after first breast cancer | 28.7 (24.4-32.9) | 19.0 (13.5-24.4) | 9.9 (8.5-11.4) |
25 years after first breast cancer | 44.1 (37.6-50.6) | 33.5 (22.4-44.7) | 17.2 (14.5-19.9) |