Table 3. Multivariate Cox proportional hazards models of OS.

	Full model			Reduced model
Characteristic	HR	95% CI	P	HR	95% CI	P
Length of tumour	1.02	0.91–1.14	0.760
Number of SUV-Avid LNs (≥1 vs 0)	1.16	0.66–2.04	0.600
Baseline T Stage (T3 vs T2)	2.13	0.71–6.35	0.180	2.70	1.17-6.22	0.020
Baseline N stage
N1 vs N0	1.07	0.19–6.08	0.940
N2/N3 vs N0	1.39	0.22–8.74	0.720
Baseline Stage (III vs I/II)	1.21	0.20–7.33	0.840
Tumour Grade (Well/Moderately Differentiated vs Poorly Differentiated)	0.44	0.26–0.72	0.001	0.41	0.25-0.67	<0.001
Treatment Arm (With IC vs Without IC)	0.85	0.53–1.36	0.490

Abbreviations: CI=confidence interval; HR=hazard ratio; LNs=lymph nodes; SUV=standard uptake value.