Table 1.
Main characteristics and results of the eligible studies
| Author and year | Sampling | Method | Antibody
|
Evaluation and cutoff value for PD-L1 positivity | PD-L1 status
|
Follow- up time (months) | Endpoints | HR estimation | HR | 95% CI | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Source | Type | Positive | Negative | |||||||||
| Eto et al10 (2015) | Tissue | IHC | Rabbit | Monoclonal | Percentage >25% | 26 | 79 | 7–87 | OS | Survival curves | 2.26 | 0.61–8.33 |
| DFS | Survival curves | 1.88 | 0.95–3.71 | |||||||||
| Kim et al16 (2014) | Tissue | IHC | Rabbit | Polyclonal | Percentage >10% | 137 | 106 | 0–123 | OS | Original text | 0.651 | 0.42–1.02 |
| DFS | Original text | 0.582 | 0.37–0.91 | |||||||||
| Hou et al11 (2014) | Tissue | IHC | Rabbit | Polyclonal | Percentage ≥10% | 70 | 41 | 7–48 | OS | Survival curves | 1.47 | 0.60–3.57 |
| Qing et al12 (2015) | Tissue | IHC | Rabbit | Polyclonal | Percentage ≥10% | 54 | 53 | 3–48 | OS | Survival curves | 2.27 | 1.21–4.26 |
| Geng et al14 (2015) | Tissue | IHC | Mouse | Monoclonal | Percentage >50% | 65 | 35 | >60 | OS | Original text | 1.65 | 1.16–2.73 |
| Wu et al13 (2006) | Tissue | IHC | Mouse | Monoclonal | NA | 43 | 59 | >42 | OS | Survival curves | 2.74 | 1.23–6.1 |
| Zheng et al17 (2014) | Serum | ELISA | NA | NA | NA | 47 | 33 | 1.5–76.6 | OS | Survival curves | 1.42 | 0.53–3.83 |
| Sun et al15 (2007) | Tissue | IHC | Mouse | Monoclonal | Percentage ≥10% | 43 | 59 | 6–31 | OS | Survival curves | 2.1 | 1.09–4.05 |
Abbreviations: CI, confidence interval; DFS, disease-free survival; ELISA, enzyme-linked immunosorbent assay; HR, hazard ratio; IHC, immunohistochemistry; NA, not available; OS, overall survival; PD-L1, programmed cell death-ligand 1.