Table 4.

Proportions of probands with a germline ancestral mutation in BRCA1 or BRCA2 out of total tested (percentages in parentheses), by personal cancer history and having a relative with breast cancer with given age at diagnosis, for first-degree relatives and for second-degree relatives

	Age at diagnosis for first-degree relatives with breast cancer				Age at diagnosis for second-degree relatives with breast cancer
Cancer status	<40 years	40–49 years	50–59 years	60 years or older	<40 years	40–49 years	50–59 years	60 years or older
No breast or ovarian cancer	3/15 (20%)	4/29 (14%)	4/34 (12%)	0/28 (0%)	1/6 (17%)	2/23 (9%)	2/19 (11%)	1/32 (3%)
Breast cancer only	3/6 (50%)	7/23 (30%)	7/21 (33%)	5/30 (17%)	3/8 (38%)	4/16 (25%)	3/24 (13%)	5/52 (10%)
Ovarian cancer only	1/1 (100%)	0/1 (0%)	0/1 (0%)	0/2 (0%)	0/0 (-)	0/2 (0%)	2/2 (100%)	1/3 (33%)
Breast and ovarian cancer	0/0 (-)	-	1/1 (100%)	-	-	-	-	-