Table 1.
Characteristics of the studies included in the meta-analysis.
| Author (yr) | Country | Sample size | Age (yr) | Study design | Treatment | Histological type | Stage | Cut off value | Survival data | NOS score |
|---|---|---|---|---|---|---|---|---|---|---|
| Bao et al (2021)[15] | China | 144 | 63 | Retrospective | Surgery | GBC | Mixed | 0.069 | OS | 6 |
| Matsumoto et al (2020)[19] | Japan | 72 | 66 | Retrospective | Surgery | ICC | Mixed | 0.020 | OS/RFS | 7 |
| Utsumi et al (2020)[20] | Japan | 53 | 73 | Retrospective | Surgery | GBC | Mixed | 0.070 | OS/RFS | 6 |
| Yasukawa et al (2020)[21] | Japan | 271 | 70 | Retrospective | Surgery | Ecca | Mixed | 0.031 | OS/RFS | 7 |
| Demir et al (2020)[23] | Turkey | 178 | 65 | Retrospective | Chemotherapy | BTC | Mixed | 0.660 | OS | 7 |
| Ito et al (2020)[22] | Japan | 82 | 65 | Retrospective | Surgery | ICC | Mixed | 0.089 | OS/RFS | 6 |
| Kano et al (2020)[18] | Japan | 88 | 68 | Retrospective | Surgery | ICC | Mixed | 0.033 | OS/RFS | 7 |
| Song et al (2021)[16] | Korea | 235 | 70 | Retrospective | Surgery | eBDC | Mixed | 0.180 | OS/RFS | 7 |
| Asakura et al (2022)[17] | Japan | 169 | 75 | Retrospective | Surgery | eCCA | Mixed | 0.230 | OS | 7 |
BTC = biliary tract cancer, eBDA = extrahepatic bile duct cancer, eCCA = extrahepatic cholangiocarcinoma, GBC = gallbladder cancer, ICC = intrahepatic cholangiocarcinoma, NOS = Newcastle-Ottawa Scale, OS = overall survival, RFS = recurrence-free survival.