Systemic immune-inflammation index is a promising non-invasive biomarker for predicting the survival of urinary system cancers: a systematic review and meta-analysis.

OBJECTIVE

Systemic immune-inflammation index (SII) has been reported in numerous studies to effectively predict the survival outcomes of urinary system cancers; however no agreement has been reached. This meta-analysis aimed to explore the prognostic significance of pre-treatment SII in tumours of the urinary system.

METHODS

Relevant published articles were selected from Web of Science, PubMed, Embase, and the Cochrane Library up to 30 August 2020. The hazard ratios (HRs) with 95% confidence intervals (CIs) were computed to estimate the associations of pre-treatment SII with overall survival (OS), progression-free survival (PFS), cancer-specific survival (CSS) in urinary system cancers.

RESULTS

13 papers were included in our meta-analysis. From the combined data, we found that a high pre-treatment SII indicated a markedly worse OS (HR = 1.98; 95% CI: 1.75-2.23;  < .001), PFS (HR: 2.08; 95% CI: 1.32-3.26;  = .002), and CSS (HR: 2.41, 95% CI: 1.73-3.35,  < .001). Additionally, patients with an elevated SII value might have undesirable pathological characteristics, including a large tumour size, a poor differentiation grade, and an advanced tumour stage (all  < .001).

CONCLUSIONS

Pre-treatment SII could be used as a non-invasive and promising biomarker to indicate the prognosis of urinary system cancer patients.KEY MESSAGES:This meta-analysis evaluates the predictive value of systemic immune-inflammation index (SII) for patients with urinary system cancer.A high pre-treatment SII indicates a poor prognosis.SII can serve as a promising non-invasive biomarker to help clinicians assess the prognosis and develop treatment strategies for urinary system cancer patients.