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.

	BRCA1	BRCA2	BRCA negative
Age at first breast cancer < 40 years
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
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
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)