Table 2.

Univariate and multivariate analysis for BCSS in patients with one to three LNs positive.

Variable	Univariate analysis		Multivariate analysis
	HR (95% CI)	P	HR (95% CI)	P
Age at diagnosis (years)
<40	Reference	–	Reference	–
40–70	0.77 (0.70–0.85)	<0.001	0.84 (0.76–0.93)	0.001
≥70	1.14 (1.07–1.22)	<0.001	1.14 (1.06–1.24)	0.001
Race
White	Reference	–	Reference	–
Black	1.52 (1.38–1.69)	<0.001	1.23 (1.11–1.37)	<0.001
Other	0.96 (0.90–1.02)	0.167	0.96 (0.90–1.02)	0.186
Marital status
Married	Reference	–	Reference	–
Unmarried	1.30 (1.21–1.40)	<0.001	1.24 (1.15–1.34)	<0.001
Tumor stage
T1	Reference	–	Reference	–
T2	1.88 (1.72–2.05)	<0.001	1.68 (1.54–1.83)	<0.001
Grade
1	Reference	–	Reference	–
2	2.07 (1.67–2.55)	<0.001	1.77 (1.43–2.19)	<0.001
3	2.01 (1.81–2.22)	<0.001	1.70 (1.53–1.89)	<0.001
ER status
Negative	Reference	–	Reference	–
Positive	0.43 (0.40–0.46)	<0.001	0.71 (0.63–0.79)	<0.001
PR status
Negative	Reference	–	Reference	–
Positive	0.45 (0.42–0.48)	<0.001	0.68 (0.61–0.76)	<0.001
No. of LNs positive
1	Reference	–	Reference	–
2	1.14 (1.04–1.24)	0.004	1.13 (1.03–1.23)	0.007
3	1.19 (1.14–1.24)	<0.001	1.19 (1.14–1.25)	<0.001
Chemotherapy
No	Reference	–	Reference	–
Yes	0.92 (0.82–1.03)	0.130	0.77 (0.68–0.86)	<0.001
Radiotherapy
No	Reference	–	Reference	–
Yes	1.02 (0.94–1.09)	0.676	0.99 (0.92–1.06)	0.715

BCSS, breast cancer–specific survival.