Table 1. Characteristics of the studies included in the meta-analysis.
| Author | Year | Country | Region | Follow-up (months) | Treatment | No. of patients | Stage | Cut-off value | Survival analysis |
Analysis | NOS score |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Shirai | 2015 | Japan | Asia | NA | Surgery | 150 | No-metastatic | 150 | OS | MV/UV | 6 |
| Smith | 2009 | UK | Europe | 12(7.8–25.5) | Surgery | 110 | No-metastatic | 150 | OS | MV | 6 |
| Qi | 2015 | China | Asia | NA | Chemotherapy | 211 | Metastatic | 126 | OS | MV/UV | 7 |
| Martin | 2014 | Austria | Europe | 12 | Mixed | 124 | Metastatic | 200 | OS | MV/UV | 8 |
| Kou | 2016 | Japan | Asia | 10.8(1.7–72.1) | Chemotherapy | 306 | Metastatic | 150 | OS | UV | 7 |
| Lnoue | 2014 | Japan | Asia | 18.7(6.1–68.2) | Mixed | 440 | Mixed | 150 | OS | MV/UV | 8 |
| Asari | 2016 | Japan | Asia | 18(10–35) | Surgery | 184 | Mixed | 225 | OS | MV/UV | 6 |
| Yamada | 2016 | Japan | Asia | 15.1(0.43–150.7) | Surgery | 379 | Mixed | 150 | OS | MV/UV | 8 |
OS: overall survival; MV: multivariate; UV: univariate; NA: not available