Preoperative albumin-to-globulin ratio as a significant prognostic indicator in urologic cancers: a meta-analysis

BACKGROUND: Emerging studies reported that preoperative albumin-to-globulin ratio (AGR) correlated with tumor progression and prognosis in several types of cancer. The aim of this study was to systematically explore the association between preoperative AGR and clinical outcomes in cancers of the urinary system. METHODS: Relevant articles were searched in PubMed, Embase and Web of Science by two independent investigators from inception to June 1, 2018. Eligible studies were selected based on predetermined selection criteria. Summarized HRs or ORs and 95% CIs were calculated for prognosis and clinicopathologic features with the fixed-effects or random-effects models. RESULTS: Eight cohort studies comprising 2,668 patients were included for analysis. The pooled results showed that a low AGR significantly correlated with poor OS (HR: 0.38, 95% CI: 0.27–0.48, P<0.001), worse cancer-specific survival (CSS) (HR: 0.36, 95% CI: 0.22–0.50, P<0.001) and inferior event-free survival (EFS) (HR: 0.36, 95% CI: 0.25–0.48, P<0.001) in urologic cancers. In addition, patients in low and high AGR groups showed significant differences in lymphovascular invasion (P<0.001), pT status (P<0.001) and pN status (P<0.001). CONCLUSION: Preoperative AGR might be a valuable, cheap and reproducible prognostic bio-marker in urologic cancers following surgical resection.