Table 4.

Cox regression association baseline variables with outcomes during radiation treatment

Overall survival	HR	Univariable	P	HR	Multivariable	P
Variables		95% CI			95% CI
Lymphocyte nadir (108 cells/L)	0.72	0.58-0.89	.003	0.75	0.58-0.96	.022
Age (1 y)	0.99	0.97-1.02	.68	NI
WCC nadir (109 cells/L)	1.02	0.83-1.27	.84	NI
Male (vs female)	1.002	0.51-1.98	.995	NI
Stage
N3 (vs N2 and N1)	0.66	0.24-1.83	.43	NI
Baseline lymphocyte	0.56	0.36-0.87	.010	0.67	0.41-1.11	.12
Chemotherapy
≥5 courses (vs <5 courses)	0.66	0.40-1.10	.11	NI
Radiation therapy
Log10 PTV	6.41	0.80-51.16	.080	5.32	0.56-50.51	.15
EDIC	1.18	0.89-1.57	.25	NI
IMRT (vs 3DCRT)	0.74	0.44-1.24	.25	NI

Recurrence-free survival	HR	Univariable	P	HR	Multivariable	P
Variables		95% CI			95% CI
Lymphocyte nadir (108 cells/L)	0.74	0.60-0.91	.004	0.78	0.62-0.99	.043
Age (1 y)	0.99	0.96-1.01	.30	NI
WCC nadir (109 cells/L)	1.01	0.82-1.23	.96	NI
Male (vs female)	1.14	0.58-2.24	.71	NI
Stage
N3 (vs N2 and N1)	0.60	0.22-1.64	.32	NI
Baseline lymphocyte	0.52	0.33-0.82	.005	0.63	0.37-1.06	.079
Chemotherapy
≥5 courses (vs <5 courses)	0.72	0.44-1.19	.20	NI
Radiation therapy
Log10 PTV	6.07	0.76-47.45	.086	4.79	0.52-44.47	.17
EDIC	1.19	0.91-1.56	.21	NI
IMRT (vs 3DCRT)	0.70	0.43-1.18	.19	NI

Abbreviations: 3DCRT = 3-dimensional conformal radiation therapy; CI = confidence interval; EDIC = effective dose to the circulating immune cells; HR = hazard ratio; IMRT = intensity modulated radiation therapy; NI = not included; PTV = planning target volume; WCC = white cell count.