Table 2.

Univariate and multivariate analyses of clinicopathological factors associated with DFS and OS

Characteristics	N	DFS		OS
		Univariate	Multivariate	Univariate	Multivariate
		P value	P value	P value	P value
		HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)
Age (years)
<63	62	0.747		0.89
≥63	75	1.09 (0.65 to 1.84)		0.96 (0.54 to 1.70)
Sex
Male	113	0.548		0.635
Female	24	1.24 (0.64 to 2.69)		1.20 (0.59 to 2.75)
Differentiation
Well or moderately	116	0.209		0.223
Poorly	21	1.66 (0.77 to 4.31)		1.71 (0.74 to 4.93)
T classification
T1 or T2	78	0.165		0.361
T3 or T4	59	0.69 (0.42 to 1.16)		0.77 (0.44 to 1.35)
N classification
N0-1	62	0.45		0.999
N2-3	75	1.21 (0.73 to 2.03)		1.00 (0.57 to 1.75)
p16
Positive	59	<0.001*		<0.001*
Negative	78	0.24 (0.12 to 0.46)		0.16 (0.06 to 0.37)
Definitive treatment
Surgery	53	0.775		0.297
CRT or RT	84	0.92 (0.55 to 1.55)		0.73 (0.40 to 1.31)
TC-PD-L1
Positive	81	0.08		*0.036	0.808
Negative	56	0.63 (0.37 to 1.06)		0.54 (0.31 to 0.96)	0.92 (0.48 to 1.76)
IC-PD-L1
Positive	83	0.008*	0.036*	<0.001*	0.010*
Negative	54	0.50 (0.29 to 0.83)	0.56 (0.33 to 0.96)	0.36 (0.20 to 0.65)	0.43 (0.22 to 0.82)
CD8
High (≥18.6)	69	0.024*	0.121	0.011*	0.119
Low (<18.6)	68	0.54 (0.32 to 0.92)	0.64 (0.37 to 1.12)	0.47 (0.25 to 0.84)	0.61 (0.31 to 1.13)

Significant differences were evaluated using a Cox proportional hazards model.

CRT, chemoradiotherapy; DFS, disease-free survival; IC-PD-L1, programmed death ligand 1 on immune cells; OS, overall survival; RT, radiotherapy; TC-PD-L1, programmed death ligand 1 on tumour cells.