Table 2.
Subgroup analysis of overall survival.
| Subgroup factor | Studies (n) | Patients (n) | HR (95% CI) | P value | Heterogeneity | |
|---|---|---|---|---|---|---|
| I2 (%) | P value | |||||
| OS | 9 | 1292 | 2.44 (1.98–2.99) | <.001 | 2 | .42 |
| Sample size | ||||||
| < 100 | 4 | 295 | 3.26 (2.05–5.21) | <.001 | 0 | .62 |
| ≥ 100 | 5 | 997 | 2.28 (1.80–2.90) | <.001 | 11 | .34 |
| Histological type | ||||||
| GBC | 2 | 197 | 3.71 (1.28–10.73) | .02 | 43 | .19 |
| ICC | 3 | 242 | 3.00 (1.85–4.88) | <.001 | 0 | .85 |
| eCCA | 2 | 440 | 1.85 (1.36–2.52) | <.001 | 0 | .93 |
| eBDA | 1 | 235 | 2.43 (1.35–4.38) | .03 | – | – |
| BTC | 1 | 178 | 3.44 (2.05–5.77) | <.001 | – | – |
| Treatment | ||||||
| Surgery | 8 | 1114 | 2.28 (1.83–2.85) | <.001 | 0 | .53 |
| Chemotherapy | 1 | 178 | 3.44 (2.05–5.77) | <.001 | – | – |
| CAR cut off value | ||||||
| < 0.070 | 4 | 575 | 2.07 (1.60–2.67) | <.001 | 0 | .79 |
| ≥ 0.070 | 5 | 717 | 3.19 (2.29–4.43) | <.001 | 0 | .50 |
BTC = biliary tract cancer, CAR = C-reactive protein-to-albumin ratio, CI = confidence interval, eBDA = extrahepatic bile duct cancer, eCCA = extrahepatic cholangiocarcinoma, GBC = gallbladder cancer, HR = hazard ratio, ICC = intrahepatic cholangiocarcinoma, OS = overall survival.