The prognostic role of preoperative serum albumin/globulin ratio in patients with bladder urothelial carcinoma undergoing radical cystectomy

Abstract

Objective: To date, only a few studies have demonstrated the prognostic value of pretreatment serum albumin in bladder urothelial carcinoma (BUC). The aim of this study was to evaluate the association between the pretreatment albumin/globulin ratio (AGR) and the survival of patients with BUC treated with radical cystectomy (RC).

Materials and methods: Data from 296 patients with BUC who underwent RC between June 2000 and June 2013 were analyzed. The AGR was calculated as follows: albumin/(total protein-albumin). The AGR was divided into 2 groups for receiver operating characteristics curve analysis. Survival was estimated using Kaplan-Meier analysis and compared using the log rank test. Cox proportional hazards models were used for univariate and multivariate survival analyses.

Results: Patients in the high AGR group (AGR≥1.60) had a lower 5-year recurrence-free mortality rate compared with those in the low AGR group (AGR<1.60) (87.0% vs. 48.0%, P<0.001). The median cancer-specific survival (CSS) time was 71.1 months for low AGR patients and 156.0 months for the high AGR patients (P<0.001). After adjusting for confounding variables, the AGR remained an independent predictor of recurrence-free survival (RFS) (hazard rate = 0.356; 95% CI: 0.170-0.748; P = 0.006) and CSS (hazard rate = 0.280; 95% CI: 0.115-0.683; P = 0.005). Moreover, in the subset of 167 patients with normal serum albumin (albumin of≥40.0g/l), serum AGR continues to be an independent predictor of RFS (P = 0.012) and CSS (P = 0.008).

Conclusions: High AGR is a strong independent predictor of long-term RFS and CSS in patients with BUC undergoing RC. Additionally, among patients with normal albumin (≥40g/l) levels, patients with higher globulin, but lower AGR have worse survival. The pretreatment AGR is an easily accessible and cheap to use for predicting mortality in patients with BUC treated by RC.

Keywords: Albumin/globulin ratio; Bladder urothelial carcinoma; Prognosis; Survival.