Table 1.

Descriptive statistics for 244 786 women with invasive female breast cancer in National Cancer Institute’s Surveillance, Epidemiology, and End Results 9 Registry Database diagnosed from January 1990 to December 2003 and followed through 2004^*

Variable	All case subjects		Blacks		Whites		P† for heterogeneity
	n	%	n	%	n	%
Age							<.001
<50	56 627	23.1	6786	33.4	44 701	21.5
50–70	105 062	42.9	8624	42.5	88 806	42.7
≥70	83 097	33.9	4894	24.1	74 428	35.8
AJCC stage							<.001
I	107 242	43.8	6208	30.6	93 587	45.0
II	81 862	33.4	7694	37.9	68 302	32.8
III	15 018	6.1	2039	10.0	12 028	5.8
IV	10 647	4.3	1444	7.1	8540	4.1
Other or unknown	30 017	12.3	2919	14.4	25 478	12.3
Tumor size							<.001
≤2.0 cm	139 543	57.0	8746	43.1	121 467	58.4
>2.0 cm	75 576	30.9	8345	41.1	61 882	29.8
Other or unknown	29 667	12.1	3213	15.8	24 586	11.8
Lymph nodes							<.001
Negative	129 680	53.0	8615	42.4	111 837	53.8
Positive	66 645	27.2	6586	32.4	55 440	26.7
Other or unknown	48 461	19.8	5103	25.1	40 658	19.6
Tumor grade							<.001
Low	117 083	47.8	6955	34.3	101 753	48.9
High	77 460	31.6	8620	42.5	63 489	30.5
Other or unknown	50 243	20.5	4729	23.3	42 693	20.5
Estrogen receptor							<.001
Not done	13 555	5.5	1393	6.9	11 403	5.5
Positive	153 068	62.5	9293	45.8	132 922	63.9
Negative	45 239	18.5	6000	29.6	35 916	17.3
Borderline	1483	0.6	149	0.7	1267	0.6
Results not on chart	8283	3.4	1062	5.2	6914	3.3
Other or unknown	23 158	9.5	2407	11.9	19 513	9.4
Persons below poverty level							<.001
<10%	144 929	59.2	5393	26.6	133 216	64.1
10–19%	95 580	39.0	17 880	88.1	70 767	34.0
≥20%	4277	1.7	31	0.2	3 952	1.9
Marital status							<.001
Never married	26 626	10.9	4652	22.9	19 936	9.6
Married	133 828	54.7	7140	35.2	116 508	56.0
Separated	1404	0.6	358	1.8	944	0.5
Divorced	22 716	9.3	3008	14.8	18 546	8.9
Widowed	52 363	21.4	4121	20.3	45 747	22.0
Other or unknown	7 849	3.2	1025	5.0	6254	3.0

^*Among 244 786 case subjects, 20 304 (8.3%) were black and 207 935 (84.9%) were white. Mean age of women in years (standard error of the mean) was 61.9 (0.03), 57.6 (0.10), and 62.7 (0.03) among all women, blacks, and whites, respectively. The corresponding median ages were 62 years, 56 years, and 63 years. N = number (or count); % = percentage of total cases. AJCC = American Joint Committee on Cancer.

^†P values from χ² test (two-sided) for heterogeneity comparing black and white women.