ABSTRACT
BACKGROUND: Systemic Immune-inflammation Index (SII) has been shown to correlate with the prognosis of numerous malignancies, but researchers have not yet reached an agreed conclusion on bladder cancer. To fill the blank, we conducted a meta-analysis to assess the prognostic role of SII in the prognosis of bladder cancer. METHODS: After analyzing relevant literature published in PubMed, China National Knowledge Infrastructure, EMBASE, Cochrane Library, and Web Science up to April 30, 2022, we collected 83 articles to assess the significance of SII levels in assessing the prognosis of bladder cancer patients, and finally, 11 articles were included in the study. The correlation between pre-treatment Systemic Immunoinflammatory Index levels and survival in bladder cancer patients was assessed using risk ratio (HR) and 95% confidence interval (CI). RESULTS: Our meta-analysis comprised 11 papers altogether, and the findings revealed that higher levels of pretreatment SII were significantly associated with poorer overall survival/cancer-specific survival/progression-free survival/recurrence-free survival in bladder cancer patients (pooled HR = 1.80; 95% CI, 1.28-2.51; pooled HR = 1.68; 95% CI, 1.14-2.47; pooled HR = 1.74; 95% CI, 1.25-2.42; pooled HR = 1.73; 95% CI, 1.26-2.39). The above result was also confirmed in the subgroup analysis. CONCLUSIONS: Higher SII levels were significantly connected with overall survival/cancer-specific survival/progression-free survival/recurrence-free survival rates in bladder cancer patients, suggesting that SII is an important predictor of prognosis in bladder cancer patients.