Table 4.

Univariate analysis of survival in the primary RT group

Variable	OS			PFS
	HR	95% CI	p-value	HR	95% CI	p-value
Age (≥65 yr)	1.00	0.37–2.76	0.993	1.02	0.38–2.75	0.965
Sex (female)	0.77	0.31–1.91	0.567	0.78	0.31–1.96	0.603
ECOG PS (≥2)	1.13	0.43–3.00	0.807	1.07	0.40–2.86	0.899
Stage (IVA vs. others)	0.03	0.00–11.7	0.253	0.03	0.00–11.8	0.253
IMRT	0.58	0.22–1.49	0.254	0.68	0.27–1.72	0.413
Chemotherapy	0.07	0.01–0.35	0.001*	0.14	0.04–0.49	0.002*
EQD210 dose (≥62 Gy)	0.16	0.05–0.53	0.003*	0.32	0.11–0.90	0.031*

RT, radiation therapy; HR, hazard ratio; CI, confidence interval; ECOG PS, Eastern Cooperative Oncology Group performance score; IMRT, intensity-modulated radiotherapy; OS, overall survival; PFS, progression-free survival.

^*p < 0.05.