Pretreatment Low Serum Sodium as a Prognostic Factor for Patients with Esophageal Cancer Treated with Radiotherapy or Chemoradiotherapy

Table 4

Cox regression analysis of clinical characteristics of progression-free survival of EC patients who underwent radiotherapy alone or chemoradiotherapy.

	Univariate			Multivariate
	HR	value	95% CI	HR	value	95% CI
KPS	1.785	0.022	1.088-2.928	1.707	0.035	1.040-2.802
70
80-90
Tumor sites
Cervical	1 (reference)
Upper	1.444	0.225	0.798-2.615
Middle	1.618	0.097	0.916-2.857
Lower	2.11	0.018	1.136-3.922
Clinical N stage
N0	1 (reference)
N1	1.623	0.298	0.652-4.038
N2-3	2.113	0.105	0.855-5.220
Clinical stage	1.689	0.002	1.220-2.338	1.846	<0.001	1.325-2.573
II-III
IV
Treatment models	0.892	0.617	0.571-1.395
Radiotherapy
Chemoradiotherapy
Serum sodium	1.594	0.005	1.149-2.213	1.744	0.001	1.248-2.437
>140 mmol/L
≤140 mmol/L

Abbreviation: EC: esophageal carcinoma; HR: hazard ratio; CI: confidence interval; KPS: Karnofsky performance status. . . .