Table 2.

Prognostic Effects of Estrogen-Receptor Status in Women with Synchronous Breast Cancers, SEER 1998-2005

	Overall Survival
Estrogen-receptor status	No. of patients	No. of patients at year 5	No. of events	Rate^a	HR (95% CI)^b
Estrogen-receptor status	No. of patients	No. of patients at year 5	No. of events	Rate^a	≤ 5 years	> 5 years

+/+	3611	2963	668	4.0	1.0 (ref)	1.0 (ref)
Discordant	422	293	133	7.5	1.96 (1.60-2.40)	0.98 (0.72-1.35)
−/−	370	229	142	9.6	2.49 (2.03-3.07)	0.84 (0.58-1.20)
P value					<0.0001	0.62

	Breast Cancer-Specific Survival
Estrogen-receptor status	No. of patients	No. of patients at year 5	No. of events	Rate^a	HR (95% CI)^b
Estrogen-receptor status	No. of patients	No. of patients at year 5	No. of events	Rate^a	≤ 5 years	> 5 years

+/+	3611	2963	491	1.8	1.0 (ref)	1.0 (ref)
Discordant	422	293	103	3.7	2.79 (2.14-3.64)	1.01 (0.62-1.65)
−/−	370	229	128	5.4	3.29 (2.54-4.26)	1.03 (0.65-1.64)
P value					<0.0001	0.99

Abbreviations: HR, hazard ratio; CI, confidence interval

Death rate per 100 person-years

Adjusted in a piecewise Cox model for age at diagnosis, race/ethnicity, marital status, AJCC stage, grade, histology of both cancers, surgery type, radiotherapy, and time interval between the two cancer

P value is from the omnibus test of comparing three groups in Cox model