TABLE 1

Characteristics of Patients and Results of Univariate and Multivariate Survival Analysis for Predicting Overall Survival

	Univariate analysis				Multivariable analysis
Characteristic	n	HR	95% CI	P	HR	95% CI	P
Age		1.304	0.991–1.709	0.127
Sex
Male	47	0.573	0.234–1.406	0.224
Female (reference)	9
Primary tumor location
Upper	6	4.275	1.266–14.441	0.019	3.208	0.894–11.512	0.074
Middle	34	2.351	0.941–5.873	0.067	1.443	0.542–3.843	0.463
Lower (reference)	16
Tumor differentiation
Well	11	0.936	0.269–3.252	0.917
Moderate	21	1.322	0.429–4.071	0.627
Poor	15	1.466	0.438–4.900	0.535
Unknown^* (reference)	9
Therapeutic modality
Surgery	26	0.318	0.145–0.694	0.004	0.437	0.195–0.979	0.044
Radiation (reference)	30
Clinical TNM stage
IIb	5	1.637	0.515–5.202	0.404
III	38	1.046	0.440–2.488	0.918
IV (reference)	13
SUV		1.105	1.038–1.176	0.002	1.071	1.007–1.139	0.029
Disease status on PET/CT
Systemic	36	2.931	1.254–6.847	0.013	2.430	1.019–5.797	0.045
Nonsystemic (reference)	20

↵* Patients were diagnosed with only cytologic proof, from which histologic grade of differentiation cannot be obtained.
HR = hazard ratio; CI = confidence interval.