Table 3. Univariate and multivariate COX regression analyses of clinical factors and independence associated with prognosis.

Variables	Univariate analysis			Multivariable analysis
	HR	95%CI of HR	P	HR	95%CI of HR	P
TCGA training datasets
6-gene risk score
Low risk group	1(reference)			1(reference)
High risk group	2.66	1.79-3.92	1.060E-06	2.18	1.04-4.53	0.038
Age	1.03	1.01-1.04	8.550E-04	0.99	0.95-1.02	0.604231
Gender female	1(reference)			1(reference)
Gender male	0.73	0.49- 1.07	0.11	0.50	0.23-1.09	0.081554
Grade 1	1(reference)			1(reference)
Grade 2	1.78	0.95-3.32	0.07	0.91	0.25-3.18	0.88025
Grade 3 / 4	1.47	0.75-2.87	0.26	1.94	0.53-7.04	0.315185
Pathologic T 1/ T 2	1(reference)			1(reference)
Pathologic T 3	2.26	1.28-3.95	4.53E-03	2.07	0.51-8.37	0.309
Pathologic T 4	2.46	1.50-4.00	3.19E-04	7.59	1.90-30.22	0.004
Pathologic N 0	1(reference)			1(reference)
Pathologic N 1	0.89	0.37-2.08	0.782	0.76	0.19-3.01	0.694
Pathologic N 2	2.29	1.40-3.72	0.001	5.02	1.97-12.75	0.001
Pathologic M 0	1(reference)			1(reference)
Pathologic M 1/ M X	1.31	0.66-2.55	0.433	1.16	0.43-3.08	0.76
Tumor stage I	1(reference)			1(reference)
Tumor stage II	1.08	0.23-4.90	0.918	0.55	0.03-9.85	0.686335
Tumor stage III	1.40	0.30-6.42	0.667	0.77	0.05-10.60	0.845959
Tumor stage IV	2.75	0.67-11.22	0.158	0.27	0.02-3.63	0.32
Validation cohort, TCGA test datasets and GSE65858
TCGA test datasets
6-gene risk score
Low risk group	1(reference)			1(reference)
High risk group	1.62	1.08- 2.42	0.020	1.45	0.67-3.12	0.339
Age	1.01	0.98-1.02	0.444	1.00	0.96-1.03	0.993
Gender female	1(reference)			1(reference)
Gender male	0.84	0.55-1.28	0.420	0.45	0.19-1.01	0.054
Grade 1	1(reference)			1(reference)
Grade 2	1.86	0.92-3.77	0.08	0.90	0.28-2.88	0.865
Grade 3	1.57	0.73-3.36	0.24	1.54	0.42-5.52	0.508
Pathologic T 1/ T 2	1(reference)			1(reference)
Pathologic T 3	1.84	1.09-3.11	0.022	1.76	0.47-6.54	0.399
Pathologic T 4	1.36	0.84-2.21	0.213	1.20	0.35-4.07	0.770
Pathologic N 0	1(reference)
Pathologic N 1	1.14	0.57-2.25	0.706	1.74	0.50-6	0.379
Pathologic N 2	2.49	1.50-4.12	0.000	1.87	0.65-5.32	0.239
Pathologic N 3	2.90	0.87-9.6	0.082	1.86	0.26-12.82	0.529
Pathologic M 0	1(reference)			1(reference)
Pathologic M 1	1.05	0.49-2.21	0.905	1.34	0.54-3.28	0.524
Tumor stage I	1(reference)
Tumor stage II	2.94	0.34-0.66	0.157	0.55	0.03-9.20	0.677
Tumor stage III	3.04	0.32-0.70	0.137	1.00	0.08-11.42	0.997
Tumor stage IV	4.03	0.24-0.98	0.053	1.46	0.12-17.69	0.765
GSE65858
6-gene risk score
Low risk group	1(reference)			1(reference)
High risk group	1.75	1.13-2.67	0.011	1.83	1.16-2.87	0.008
Age	1.03	1.00-1.04	0.01	1.03	1.01-1.05	0.00
Gender female	1(reference)			1(reference)
Gender male	1.05	0.61-1.77	0.87	1.02	0.59-1.75	0.94
Pathologic T 1	1(reference)			1(reference)
Pathologic T 2	0.49	0.21-1.15	0.10	0.53	0.15-1.78	0.31
Pathologic T 3	1.73	0.81-3.67	0.15	1.61	0.55-4.69	0.38
Pathologic T 4	1.89	0.91-3.87	0.08	1.22	0.42-3.53	0.71
Pathologic N 0	1(reference)			1(reference)
Pathologic N 1	0.36	0.12-1.02	0.06	0.34	0.10-1.08	0.07
Pathologic N 2	1.60	0.99-2.56	0.05	1.03	0.51-2.05	0.94
Pathologic N 3	2.93	1.34-6.42	0.01	1.27	0.41-3.84	0.67
Pathologic M 0	1(reference)			1(reference)
Pathologic M 1/ M X	3.71	1.63-8.4	0.00	2.18	0.70-6.79	0.18
Tumor stage I	1(reference)			1(reference)
Tumor stage II	0.39	0.11-1.33	0.13	0.60	0.10-3.40	0.56
Tumor stage III	0.46	0.14-1.45	0.19	0.66	0.13-3.31	0.61
Tumor stage IV	1.49	0.60-3.70	0.39	1.14	0.24-5.20	0.87