The prognostic significance of PD-L1 and PD-1 expression in patients with nasopharyngeal carcinoma: a systematic review and meta-analysis

Table 4 The relationship between clinicopathological factors and the expression level of (a) PD-L1 in NPCs, (b) PD-1 in NPCs

Clinicopathological factors	RR	95% CI	p value	Heterogeneity		No. of studies	Statistical model used
Clinicopathological factors	RR	95% CI	p value	I² (%)	p value	No. of studies	Statistical model used
(a)
Gender: male	1.02	(0.96, 1.09)	0.45	0	0.70	13	Fixed
T stage ≥ 3	1.00	(0.89, 1.13)	0.88	42	0.07	11	Random
N stage ≥ 2	0.98	(0.87, 1.10)	0.77	34	0.12	11	Fixed
Metastasis	0.83	(0.52, 1.33)	0.45	0	0.45	4	Fixed
Stage III or IV	1.07	(0.99, 1.15)	0.08	38	0.12	9	Fixed
Undifferentiated	0.99	(0.84, 1.18)	0.94	54	0.07	5	Random
Tobacco use: smoker	0.91	(0.78, 1.07)	0.24	0	0.43	8	Fixed
Alcohol use: drinker	0.73	(0.49, 1.09)	0.13	0	0.63	2	Fixed
EBV positive	1.03	(0.93, 1.15)	0.54	29	0.24	2	Fixed
(b)
Gender: male	1.04	(0.96, 1.13)	0.35	0	0.99	6	Fixed
T stage ≥ 3	0.93	(0.81, 1.07)	0.29	0	0.66	4	Fixed
N stage ≥ 2	1.11	(0.95, 1.29)	0.20	0	0.97	5	Fixed
Stage III or IV	1.02	(0.94, 1.10)	0.65	29	0.23	5	Fixed
Tobacco use: smoker	1.10	(0.85, 1.43)	0.46	0	0.85	3	Fixed
PD-L1 positive	1.25	(1.02, 1.52)	0.03	0	0.80	4	Fixed

RR: relative risk; CI: confidence interval; No: number; NPC: nasopharyngeal carcinoma; EBV: Epstein–Barr virus

ISSN: 1475-2867