Table 2.

Hazard ratio of overall survival for patients with Ewing sarcoma based on Cox regression

Characteristics	Univariate analysis	95% CI	P value	Multivariable analysis	95% CI	P value
	Hazard ratio			Hazard ratio
Age (years)
≤ 18	Reference			Reference
19–27	1.928	1.200–3.097	0.007	1.778	1.092–2.895	0.021
≥ 28	5.324	3.434–8.254	<0.001	5.145	3.231–8.192	<0.001
Sex
Male	Reference			Not included
Female	1.026	0.700–1.502	0.897
Race
White	Reference			Not included
Black	1.828	0.887–3.767	0.102
Others/unknown	1.075	0.560–2.066	0.827
stage
II	Reference			Reference
III	2.022	0.276–14.793	0.488	2.545	0.289–28.446	0.400
IV	3.266	2.142–4.977	<0.001	1.100	0.117–10.312	0.933
Others/unknown	2.144	1.168–3.937	0.014	1.195	0.484–2.945	0.699
T stage
T0-T1	Reference			Reference
T2	1.384	0.857–2.234	0.184	1.284	0.769–2.144	0.340
T3	3.905	1.845–8.264	<0.001	1.367	0.558–3.347	0.494
Tx	2.558	1.565–4.181	<0.001	1.453	0.731–2.888	0.286
N stage
N0	Reference			Reference
N1	1.335	0.646–2.758	0.436	0.686	0.258–1.825	0.450
Nx	3.188	1.912–5.312	<0.001	3.392	1.848–6.224	<0.001
M stage
M0	Reference			Reference
M1	2.992	2.055–4.356	<0.001	1.981	0.205–19.147	0.555
Bone metastasis
No/unknown	Reference			Reference
Yes	3.476	2.271–5.320	<0.001	2.309	1.315–4.056	0.004
Brain metastasis
No/unknown	Reference			Not included
Yes	3.087	0.979–9.735	0.054
Liver metastasis
No/unknown	Reference			Reference
Yes	8.918	2.801–28.390	<0.001	2.861	0.651–12.564	0.164
Lung metastasis
No/unknown	Reference			Reference
Yes	2.121	1.393–3.227	<0.001	1.226	0.699–2.148	0.477