Table 3 The relationship between PD-L1 expression and clinicopathological characteristics in subgroup analysis
Subgroup analysis | No. of studies | No. of patients | Experimental group: positive/total | Control group: positive/total | OR | 95%CI | P value | Heterogeneity (I2), % | Begg’s test (P value) | Egger’s test (P value) |
|---|---|---|---|---|---|---|---|---|---|---|
Gender | 9 | 3706 | Male | Female | 0.92 | 0.79–1.07 | 0.29 | 0 | 0.917 | 0.639 |
898/1852 | 1018/1854 | |||||||||
The situation of primary tumor | 7 | 2809 | T3+T4 | T1+T2 | 1.15 | 0.68–1.95 | 0.60 | 70 | 0.764 | 0.115 |
1018/2176 | 347/633 | |||||||||
The involvement of regional lymph nodes | 6 | 2652 | N1+N2 | N0 | 1.32 | 0.84–2.09 | 0.23 | 74 | 0.060 | 0.012 |
558/1225 | 729/1427 | |||||||||
Stage | 6 | 2064 | III+IV | I+II | 1.77 | 1.41–2.23 | P < 0.00001 | 23 | 0.452 | 0.512 |
594/936 | 659/1128 | |||||||||
Vascular invasion | 6 | 2052 | Positive | Negative | 1.12 | 0.72–1.75 | 0.62 | 63 | 0.133 | 0.090 |
201/564 | 491/1488 | |||||||||
Tumor location | 6 | 3133 | Left | Right | 0.86 | 0.53–1.40 | 0.55 | 82 | 0.452 | 0.283 |
916/1873 | 711/1260 | |||||||||
Microsatellite instability | 4 | 2012 | MSI-H | MSI-L+MSS | 0.95 | 0.46–1.97 | 0.89 | 84 | 1.000 | 0.347 |
223/362 | 1012/1650 | |||||||||
Lymphatic invasion | 4 | 723 | Positive | Negative | 3.49 | 1.54–7.90 | 0.003 | 73 | 1.000 | 0.764 |
122/280 | 83/443 | |||||||||
Tumor differentiation | 4 | 1862 | Poor | Well to moderate | 1.90 | 0.55–6.63 | 0.31 | 88 | 0.734 | 0.292 |
108/156 | 1057/1706 | |||||||||
Mucinous properties | 3 | 1563 | Mucinous | Other | 0.94 | 0.42–2.10 | 0.88 | 56 | – | – |
34/108 | 573/1455 | |||||||||
Grade | 3 | 1562 | III | I+II | 0.66 | 0.42–1.03 | 0.07 | 52 | – | – |
86/239 | 569/1323 |