Table 4.

Associations between race and mortality before and after adjusting for ER staining levels in multivariable models among 1573 women with ER+/HER2− invasive breast cancer

	Overall mortalitya						Breast cancer-specific mortalityb
	Model 1c			Model 1 + adjustment for % ER			Model 2d			Model 2 + adjustment for % ER
	HR	95% CI	p-value	HR	95% CI	p-value	HR	95% CI	p-value	HR	95% CI	p-value
Race (AAW vs. EAW)	1.75	1.32–3.32	< 0.001	1.72	1.29–2.30	< 0.001	1.48	0.99–2.21	0.054	1.45	0.96–2.20	0.080
Age at diagnosis (years)	1.03	1.01–1.04	< 0.001	1.03	1.02–1.04	< 0.001	1.01	0.99–1.02	0.43	1.01	0.99–1.02	0.20
Grade (2 vs 1)	1.75	1.13–2.72	0.012	1.70	1.10–2.64	0.018	4.26	1.53–11.8	0.54	3.85	1.38–10.8	0.0010
Grade (3 vs 1)	2.29	1.44–3.67	< 0.001	2.07	1.28–3.34	0.003	6.54	2.32–18.5	< 0.001	5.36	1.88–15.3	0.0017
Node involvement (yes vs no)	2.23	1.41–3.54	< 0.001	2.74	1.70–4.42	< 0.001	1.43	0.66–3.10	0.36	2.22	0.95–5.17	0.061
Stage (regional vs. local)	0.89	0.55–1.45	0.65	0.78	0.47–1.28	< 0.001	1.71	0.75–3.91	0.20	1.35	0.56–3.25	0.50
Stage (distant vs. local)	9.21	5.40–15.7	< 0.001	8.59	5.01–14.7	0.32	31.8	13.4–72.5	< 0.001	27.5	11.4–66.3	< 0.001
Stage (unknown vs. local)	2.66	1.37–5.16	0.004	2.77	1.38–5.56	0.004	3.61	1.18–11.0	0.024	4.38	1.35–14.2	0.014
ET (yes vs. no)	0.30	0.22–0.41	< 0.001	0.35	0.25–0.49	< 0.001	0.18	0.12–0.28	< 0.001	0.23	0.14–0.38	< 0.001
Chemo (yes vs. no)	0.84	0.61–1.16	0.29	0.85	0.61–1.20	0.36	1.02	0.66–1.59	0.92	1.00	0.62–1.62	0.99
ER (1–50% vs. > 50%)				1.57	0.94–2.58	0.083				2.11	1.14–3.87	0.017

^aTotal number of deaths = 228

^bTotal number of deaths due to breast cancer = 110

^cModel 1 evaluates the effect of race on overall mortality adjusting for age, grade, node involvement, stage, endocrine therapy, and chemotherapy

^dModel 2 evaluates the effect of race on breast cancer-specific mortality adjusting for age, grade, node involvement, stage, endocrine therapy, and chemotherapy