Table 4.
The prognostic value of SII for PFS in cancer patients treated with ICIs.
| Subgroups | No. of studies | No. of patients | Effects model | HR (95%CI) | p | Heterogeneity I2 (%) Ph |
|
|---|---|---|---|---|---|---|---|
| Overall | 14 | 1464 | Random | 2.09(1.48–2.95) | <.001 | 80.2 | <0.001 |
| Study design | |||||||
| Prospective | 2 | 296 | Random | 2.36(1.33–4.20) | .004 | 54.6 | 0.138 |
| Retrospective | 12 | 1168 | Random | 2.02(1.37–2.98) | <.001 | 75.7 | <0.001 |
| Sample size | |||||||
| <100 | 7 | 335 | Fixed | 2.78(1.96–3.93) | <.001 | 23.0 | 0.254 |
| ≥100 | 7 | 1129 | Random | 1.68(1.15–2.44) | .007 | 80.8 | <0.001 |
| Study centre | |||||||
| Single centre | 11 | 1094 | Random | 2.02(21.34–3.03) | .001 | 77.4 | <0.001 |
| Multicentre | 3 | 370 | Fixed | 2.04(1.55–2.70) | <.001 | 27.0 | 0.254 |
| TNM stage | |||||||
| III–IV | 7 | 870 | Random | 2.06(1.40–3.03) | <.001 | 55.8 | 0.035 |
| IV | 6 | 553 | Random | 2.32(1.25–4.30) | .007 | 82.8 | <0.001 |
| I–IV | 1 | 41 | – | 0.38(0.04–3.48) | .392 | – | – |
| ICIs type | |||||||
| Anti-PD-1 | 8 | 983 | Random | 2.15(1.30–3.55) | .003 | 82.0 | <0.001 |
| Anti-PD-1/PD-L1 | 2 | Fixed | 1.31(0.87–1.96) | .201 | 19.6 | 0.265 | |
| Anti-PD-1/PD-L1 + Anti-CTLA-4 | 1 | 122 | – | 2.84(1.03–7.82) | .043 | – | – |
| Anti-PD-1 + Anti-CTLA-4 | 2 | 92 | Fixed | 4.44(1.83–10.78) | .001 | 0 | 0.365 |
| Anti-PD-L1 | 1 | 267 | – | 1.91(1.39–2.63) | <.001 | – | – |
| Cut-off value of SII | |||||||
| <800 | 7 | 498 | Random | 2.40(1.47–3.93) | <.001 | 51.5 | 0.054 |
| ≥800 | 7 | 966 | Random | 1.87(1.20–2.93) | .006 | 83.7 | <0.001 |
| Country | |||||||
| Asian | 11 | 1119 | Random | 1.92(1.30–2.83) | .001 | 74.8 | <0.001 |
| Non-Asian | 3 | 345 | Fixed | 2.19(1.66–2.91) | <.001 | 39.2 | 0.193 |
| Survival analysis | |||||||
| Univariate | 6 | 398 | Fixed | 2.01(1.44–2.81) | <.001 | 48.7 | 0.083 |
| Multivariate | 8 | 1066 | Random | 2.13(1.38–3.28) | .001 | 84.1 | <0.001 |
| Cancer type | |||||||
| NSCLC | 2 | 73 | Fixed | 3.84(2.13–6.93) | <.001 | 0 | 0.744 |
| Esophageal cancer | 2 | 188 | Fixed | 1.27(0.71–2.26) | .425 | 0 | 0.545 |
| Gastric cancer | 2 | 245 | Fixed | 1.46(1.01–2.12) | .042 | 0 | 0.525 |
| RCC | 2 | 92 | Fixed | 4.44(1.83–10.78) | .001 | 0 | 0.365 |
| BTC | 1 | 60 | – | 2.24(1.25–4.02) | .007 | – | – |
| Urothelial carcinoma | 1 | 267 | – | 1.91(1.39–2.63) | <.001 | – | – |
| HCC | 1 | 110 | – | 7.11(2.37–21.31) | <.001 | – | – |
| Melanoma | 1 | 266 | – | 1.04(0.97–1.11) | .254 | – | – |
| Pancreatic cancer | 1 | 122 | – | 2.84(1.03–7.82) | .043 | – | – |
| SCLC | 1 | 41 | – | 0.38(0.04–3.48) | .392 | – | – |
Note: SII: Systemic Immune-Inflammation Index; PFS: progression-free survival; ICIs: immune checkpoint inhibitors; NSCLC: non-small cell lung cancer; RCC: renal cell carcinoma; BTC: biliary tract cancer; HCC: hepatocellular carcinoma; SCLC: small cell lung cancer.