Table 3.

Multivariate Cox Proportional Hazard Model for 10-Year Disease-Free Survival (DFS) using 1D5 or SP1 to determine ER Status

	ER Status determined by 1D5 n = 225			ER Status determined by SP1 n = 225
Characteristic	HR	95% CI	P	HR	95% CI	P
Age at diagnosis, years
<50 vs.≥50	0.990	0.607–1.615	0.9676	0.976	0.597–1.595	0.9220
Nodal status
Positive vs. negative	0.481	0.308–0.752	0.0013	0.475	0.303–0.744	0.0012
Tumor size, mm
≤2 vs. ≥5	0.287	0.160–0.516	< 0.0001	0.308	0.171–0.556	< 0.0001
2–5 vs. ≥5	0.483	0.292–0.799	0.0046	0.488	0.294–0.810	0.0055
Nuclear Grade
1 vs. 3	0.855	0.430–1.700	0.6547	0.887	0.441–1.783	0.7365
2 vs. 3	0.983	0.617–1.564	0.9413	0.963	0.603–1.538	0.8745
ER status
Positive vs. negative	1.943	1.230–3.069	0.0044	1.994	1.220–3.259	0.0059

Overall model is significant with 1D5 (Chi-Square = 44.169, Wald P-value = <0.0001) and with SP1 (Chi-Square = 44.319, Wald P-value = <0.0001). ER, estrogen receptor; HR, adjusted hazard ratio; DFS, disease-free survival