Systemic Immune–Inflammation Index Predicts Prognosis of Cancer Immunotherapy: Systemic Review and Meta-Analysis

Objective: This meta-analysis was designed to explore the association between the systemic immune-inflammation index (SII) and the therapeutic effect of immune checkpoint inhibitors. Materials 95% CI: 2.04-2.82; PFS HR = 1.57; 95% CI: 1.33-1.86) and that an SII value of 750 was appropriate as a cut-off value (OS HR = 2.20; 95% CI: 1.83-2.63; PFS HR = 1.54; 95% CI: 1.33-1.80). Conclusion: High SII levels (>750) may be an indicator of worse OS and PFS in cancer patients treated with immune checkpoint inhibitors.