Table 1.

Relationships between p16 or PD-L1 expression and patient characteristics

Characteristics	No of patients (%)	p16		P value	TC-PD-L1		P value	IC-PD-L1		P value
		Negative (%)	Positive (%)		<5% (%)	≥5% (%)		<5% (%)	≥5% (%)
	137	78 (56.9)	59 (43.1)		56 (40.9)	81 (59.1)		54 (39.4)	83 (60.6)
Age (years)				0.083			0.728			0.728
<63	62 (45.3)	30	32		24	38		22	40
≥63	75 (54.7)	48	27		32	43		32	43
Sex				0.5			0.039*			0.358
Male	113 (82.5)	66	47		51	62		47	66
Female	24 (17.5)	12	12		5	19		7	17
Smoking status				0.019*			0.201			*0.016
No	33 (24.1)	14	19		10	23		8	25
Yes	98 (71.5)	58	40		42	56		41	57
Unknown	6 (4.4)	6	0		4	2		5	1
Alcohol status				0.001*			0.07			*0.007
No	39 (28.5)	15	24		12	27		11	28
Yes	90 (65.7)	55	35		38	52		36	54
Unknown	8 (5.8)	8	0		6	2		7	1
Differentiation				0.007*			0.008*			*0.008
Well or moderately	116 (84.7)	72	44		53	63		52	64
Poorly	21 (15.3)	6	15		3	18		2	19
cT stage				0.605			1			0.861
T1 or T2	78 (56.9)	46	32		32	46		30	48
T3 or T4	59 (43.1)	32	27		24	35		24	35
cN stage				0.001*			0.038*			0.861
N0 or N1	61 (44.5)	44	17		31	30		25	36
N2 or N3	76 (55.5)	34	42		25	51		29	47
cStage				<0.001*			0.012*			0.532
I or II	31 (22.6)	27	4		19	12		14	17
III or IV	106 (77.4)	51	55		37	69		40	66
Definitive treatment				0.216			0.032*			0.477
Surgery	53 (38.7)	34	19		28	25		23	30
CRT or RT	84 (61.3)	44	40		28	56		31	53

CRT, chemoradiotherapy; IC-PD-L1, programmed death ligand 1 on immune cells; RT, radiotherapy; TC-PD-L1, programmed death ligand 1 on tumour cells.