Table 3.

Overall survival univariate and multivariate analysis.

Variable	Univariate analysis		Multivariate analysis
	Hazard ratio	P value	Hazard ratio	P value
T stage (4 vs. 1–3)	1.17 (0.87–1.58)	0.31
N stage (2–3 vs. 0–1)	1.39 (1.02–1.90)	0.04	1.72 (1.24–2.39)	0.001
Overall stage (4 vs. 1–3)	1.32 (0.98–1.78)	0.07
Initial site
Other	(reference)		(reference)
Nasopharynx	0.50 (0.32–0.79)	0.003	0.50 (0.30–0.81)	0.005
Oral cavity	1.54 (1.07–2.20)	0.02	1.81 (1.22–2.68)	0.003
Histology (SCC vs. other)	1.48 (0.99–2.18)	0.05
Number of recurrences (1 vs. ≥2)	0.71 (0.53–0.95)	0.02
Time since first radiation therapy	0.90 (0.81–0.99)	0.04
Gender (male vs. female)	0.93 (0.69–1.27)	0.65
Age (>70 vs. <70)	1.17 (0.83–1.63)	0.37
KPS (≥80 vs. <80)	0.38 (0.26–0.56)	<0.001	0.41 (0.27–0.63)	<0.001
Organ dysfunction	2.19 (1.57–3.06)	<0.001	1.89 (1.31–2.75)	<0.001
Charlson score (>2 vs. ≤1)	1.00 (0.67–1.48)	0.98
Surgery	0.57 (0.43–0.77)	<0.001	0.37 (0.27–0.52)	<0.001
Concurrent chemotherapy	1.20 (0.88–1.62)	0.26
Radiation type (IMRT vs. other)	0.72 (0.52–1.00)	0.05
Radiation dose (>50 Gy vs. ≤50 Gy)	0.72 (0.52–0.98)	0.04	0.65 (0.47–0.92)	0.01

IMRT, image-guided radiation therapy; KPS, Karnofsky performance status; SCC, squamous cell cancer.