Prognostic Effect of Albumin-to-Globulin Ratio in Patients with solid tumors: A Systematic Review and Meta-analysis

Background: Albumin and globulin are main components of serum protein. The level of albumin and globulin partially represents the nutrition status and immune system. Albumin-to-globulin ratio (AGR) has been reported as a prognostic factor in various cancers. We therefore performed a meta-analysis to elucidate the prognosis effect of AGR on survival outcomes in solid tumors. Method: Six electronic database were searched for the relevant articles that assessing the prognostic value of pre-treatment AGR in solid tumor patients. The primary outcome was overall survival (OS) and the secondary outcomes were cancer-specific survival (CSS), disease-free survival (DFS) and disease-metastasis-free survival (DMFS). The time-to-event outcomes were summarized in hazard ratio (HR) and 95% confidence interval (CI). Result: A total of 13890 solid tumor patients in 24 studies were included. The AGR higher than the cut-off values ranging from 1.15-1.75 was related to better OS (HR=0.58, 95%CI 0.537-0.626, p<0.0001), CSS (HR=0.287, 95%CI 0.187-0.438, p<0.0001), DFS (HR=0.792, 95%CI 0.715-0.878, p<0.0001) and DMFS (HR=0.595, 95%CI 0.447-0.792, p<0.0001). According to the cut-off values, subgroup analysis showed that AGR had significant prognostic effect on OS in each cut-off intervals (≤1.20, 1.20-1.40 and ≥1.40). Conclusion: Pre-treatment AGR is an effective prognostic factor and high AGR represents an ideal clinical outcome in the solid tumor patients.