Table 3. Univariate and multivariate cox regression analyses of factors affecting overall patient survival of 3-year.

Variable	Univariate				Multivariate
	P	HR	95% CI		P	HR	95% CI
Chemotherapy	0.07	1.473	0.967, 2.246		0.12	1.511	0.903, 2.528
Gender, vs. female
Male	0.14	1.415	0.895, 2.239		0.26	1.394	0.778, 2.498
Age (years)
≤50	0.27				0.38
51–74	0.20	1.658	0.763, 3.601		0.22	1.725	0.716, 4.152
≥75	0.11	2.14	0.853, 5.371		0.18	2.127	0.709, 6.384
Race
White	0.81
Black	0.79	0.909	0.447, 1.848
Hispanic	0.92	1.028	0.585, 1.805
Asian	0.37	0.783	0.462, 1.329
Marriage
Unmarried	0.60
Married	0.71	1.125	0.607, 2.085
Divorced/separated/widowed	0.34	1.451	0.671, 3.138
T stage
T1	<0.001				0.004
T2	0.001	2.597	1.489, 4.532		0.01	2.117	1.174, 3.819
T3	<0.001	3.487	1.846, 6.588		0.002	3.173	1.528, 6.587
T4	<0.001	4.157	2.006, 8.614		0.007	3.262	1.389, 7.662
N stage, vs. N0
N1	0.02	2.361	1.132, 4.928		0.22	1.738	0.715, 4.228
M stage, vs. M0
M1	0.17	1.797	0.78, 4.141		0.57	0.735	0.257, 2.106
Household income (dollar)
<55,000	0.73
55,000–75,000	0.99	0.996	0.533, 1.863
>75,000	0.60	0.847	0.454, 1.58
Radiotherapy	0.28	0.048	<0.001, 12.304		0.97	<0.001	<0.001, >999

CI, confidence interval; HR, hazard ratio; M, metastasis; N, node; T, tumor.