Table 1.

Sample Characteristics, Individual-Level Measures

	Percent with Characteristic				Census Sample		Census Sample
	Full Sample		Census Sample		With LND		Without LND
	N	%	N	%	N	%	N	%	p
Total	1051		1000		349	34.9	651	65.1
Age (years)									< 0.001
Less than 40	54	5.1	49	4.9	27	7.7	22	3.4
40 to 54	241	22.9	230	23.0	92	26.4	138	21.2
55 to 64	376	35.8	357	35.7	121	34.7	236	36.3
65+	380	36.2	364	36.4	109	31.2	255	39.2
Calendar Year of Diagnosis									< 0.001
Before 1987	35	3.3	34	3.4	29	8.3	5	0.8
1998–1991	107	10.2	104	10.4	63	18.1	41	6.3
1992–1993	124	11.8	117	11.7	51	14.6	66	10.1
1994–1995	162	15.4	152	15.2	43	12.3	109	16.7
1996–1998	451	42.9	426	42.6	121	34.7	305	46.9
1999–2000	172	16.4	167	16.7	42	12.0	125	19.2
Insurance									< 0.001
Medicare	324	30.8	307	30.7	90	25.8	217	33.3
Private	537	51.1	508	50.8	194	55.6	314	48.2
Medicare + Private	106	10.1	102	10.2	37	10.6	65	10.0
Medicaid/uninsured/other	18	1.7	18	1.8	5	1.4	13	2.0
Unknown	66	6.3	65	6.5	23	6.6	42	6.5
Comorbidity†
Osteoarthritis	191	18.2	178	17.8	59	16.9	119	18.3	0.59
Asthma	67	6.4	65	6.5	22	6.3	43	6.6	0.85
Depression	76	7.2	71	7.1	20	5.7	51	7.8	0.22
Diabetes with insulin	49	4.7	49	4.9	13	3.7	36	5.5	0.21
Diabetes no insulin	24	2.3	23	2.3	6	1.7	17	2.6	0.37
Congestive heart failure	29	2.8	29	2.9	6	1.7	23	3.5	0.10
Hypertension	380	36.2	362	36.2	116	33.2	246	37.8	0.15
Smoking	171	16.3	162	16.2	49	14.0	113	17.4	0.17
Thyroid	121	11.5	119	11.9	39	11.2	80	12.3	0.6
Race									< 0.001
White	835	79.4	794	79.4	283	81.1	511	78.5
Black	158	15.0	151	15.1	47	13.5	104	16.0
Asian	10	1.0	9	0.9	5	1.4	4	0.6
Unknown	47	4.5	46	4.6	14	4.0	32	4.9
Histologic Subtype
Comedo	333	31.7	314	31.4	138	39.5	176	27.0	< 0.001
Cribiform	382	36.3	364	36.4	105	30.1	259	39.8	< 0.001
Apocrine	10	1.0	9	0.9	4	1.1	5	0.8	0.55
Other	23	2.2	22	2.2	12	3.4	10	1.5	0.05
Unknown	50	4.8	50	5.0	10	2.9	40	6.1	0.02
Papillary	44	4.2	43	4.3	9	2.6	34	5.2	0.05
Micropapillary	74	7.0	70	7.0	17	4.9	53	8.1	0.05
Nuclear Grade									< 0.001
Low	139	13.2	131	13.1	19	5.4	112	17.2
Intermediate	199	18.9	196	19.6	47	13.5	149	22.9
High	436	41.5	409	40.9	162	46.4	247	37.9
Unknown	277	26.4	264	26.4	121	34.7	143	22.0
Multifocal	358	34.1	342	34.2	135	38.7	207	31.8	0.03
Surgical Treatment									< 0.001
Mastectomy	414	39.4	395	39.5	306	87.7	89	13.7
Reconstruction									< 0.001
Implant	65	6.2	62	6.2	42	13.7	20	22.5	< 0.001
Autogenous	97	9.2	95	9.5	77	22.1	18	2.8	< 0.001
None	233	22.2	220	22.0	182	59.5	38	42.7	< 0.001
Unknown	7	0.7	6	0.6	5	1.6	1	1.1	0.01
Breast Conserving Surgery	637	60.6	605	60.5	43	12.3	562	86.3
Site Dummy	638	60.7	604	60.4	246	70.5	358	55.0	< 0.001

^†Some patients have more than one comorbid condition