Table 1.

Characteristics of Triple Negative Cases and Controls, by Age, Breast Cancer and Etiology in Minorities (BEM) Study

	Women Aged <50 Years				Women Aged ≥50 Years
	TNBC Cases n=252		Controls n=2,223		TNBC Cases n=306		Controls n=2,888
	n	%1	n	%1	n	%1	n	%1
Study2
AABCS	21	8	947	43	44	14	949	33
NC-BCFR	201	80	323	15	229	75	303	10
SFBCS	30	12	953	43	33	11	1,636	57
Time period3
1995–1999	62	25	1,182	53	27	9	1,696	59
2000–2004	77	31	903	41	101	33	1,005	35
2005–2009	113	45	138	6	178	58	187	6
Race/ethnicity
African American	38	15	227	10	64	21	414	14
Asian American	54	21	1,007	45	84	27	982	34
Hispanic	85	34	611	27	69	23	887	31
Non-Hispanic white	75	30	378	17	89	29	605	21
Age (years)
<40	97	38	597	27	0	0	0	0
40–49	155	62	1,626	73	0	0	0	0
50–59	0	0	0	0	213	70	1,518	53
60–75	0	0	0	0	93	30	1,370	47
Education
Some high school or less	29	12	369	17	41	13	738	26
High school degree	29	12	284	13	47	15	517	18
Technical/vocational school or some college	81	32	581	26	104	34	724	25
College or higher degree	113	45	989	44	114	37	909	31
Country of birth
U.S.-born	157	62	1,006	45	198	65	1,553	54
Foreign-born	95	38	1,217	55	108	35	1,335	46
Family history of breast cancer in first-degree relatives
No	195	77	2,032	92	238	78	2,538	89
Yes	57	23	182	8	67	22	327	11
Unknown4	0	0	9	0	1	0	22	1
Personal history of benign breast disease
No	227	90	1,866	84	241	79	2,175	75
Yes	25	10	357	16	65	21	709	25
Unknown4	0		0		0		4
Alcohol consumption in reference year (drinks/week)
0	171	68	1,396	63	205	67	1,939	67
≤2.0	18	7	346	16	22	7	405	14
>2.0	62	25	481	22	77	25	542	19
Unknown4	1		0		2		2
Height (cm, quartiles)5
<154.9	25	10	472	21	45	15	842	29
155.0–159.9	52	21	742	33	86	28	929	32
160.0–165.0	90	36	502	23	78	26	621	22
>165.0	83	33	504	23	95	31	487	17
Unknown4	2		3		2		9
Body mass index (kg/m2) in reference year
<25	128	51	1,303	59	125	41	1,244	43
25–29.9	68	27	505	23	79	26	877	31
≥30	53	21	411	19	100	33	754	26
Unknown4	3		4		2		13
Oral contraceptive use
Never	54	21	712	32	85	28	1,361	48
Former	158	63	1,378	62	218	71	1,497	52
Current	40	16	126	6	3	1	7	0
Unknown4			7				23
Menopausal status in reference year
Premenopausal	209	87	1,881	90	41	14	270	10
Postmenopausal	32	13	211	10	256	86	2,467	90
Unknown4	11		131		11		151
Hormone therapy use (postmenopausal women)
Never	25	78	107	51	137	54	1,181	48
Former	3	9	49	23	79	31	739	30
Current	4	13	53	25	36	14	528	22
Unknown4	0		2		4		19

¹Percentages may not add up to 100 due to rounding.

²AABCS: Los Angeles County Asian Breast Cancer Study; NC-BCFR: Northern California site of the Breast Cancer Family Registry; SFBCS: San Francisco Bay Area Breast Cancer Study.

³Year of diagnosis for cases, year of selection or interview for controls.

⁴Not included in percentages.

⁵Quartiles among all controls.