Prognostic and clinicopathological value of Ki-67/MIB-1 expression in renal cell carcinoma: a meta-analysis based on 4579 individuals

Background Previous studies have investigated the prognostic significance of Ki-67/MIB-1 expression in renal cell carcinoma (RCC), however, the reports are controversial and inconsistent. This study aimed to investigate Ki-67/MIB-1 expression in RCC and its correlation with prognosis and clinicopathological features. Methods We searched relevant studies that reported associations between Ki-67/MIB-1 expression and prognosis in RCC from PubMed, Embase, Web of Science, and Cochrane Library studies published until April 14, 2017. Hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted from eligible studies. Fixed and random effects models were used to calculate pooled HRs and 95% CIs according to heterogeneity. Results A total of 4579 participants from 23 eligible studies were included in this analysis. The results showed that Ki-67/MIB-1 expression was associated with poor overall survival (HR=2.06, 95% CI: 1.64-2.57) and cancer specific survival (HR=2.01, 95% CI: 1.66-2.44). In addition, Ki-67/MIB-1 expression was also correlated with TNM stage (III/IV vs I/II: OR=1.92, 95% CI: 1.61-2.28), pathological T stage (pT3/pT4 vs pT1/pT2: OR=1.56, 95% CI: 1.21-2.02), distant metastasis (M1 vs M0: OR=1.81, 95% CI: 1.34-2.43), and Fuhrman grade (III/IV vs I/II: OR=1.94, 95% CI: 1.21-3.10). Conclusion Our study demonstrates that the presence of high Ki-67/MIB-1 expression and advanced clinicopathological features were correlated with poor prognosis in RCC patients.