Docetaxel-based therapy with and without antiangiogenic agents as first-line chemotherapy for castration-resistant prostate cancer: A meta-analysis of nine randomized controlled trials

The aim of this study was to systematically assess the effectiveness and safety of the addition of antiangiogenic agents to docetaxel-based chemotherapy for the treatment of castration-resistant prostate cancer. Computerized electronic databases, including Embase, PubMed and The Cochrane Library were searched for randomized controlled trials (RCTs) on the comparison between docetaxel-based therapy with and without antiangiogenic agents for the treatment of prostate cancer. The search time limit was from the building of the database until July 18, 2013. Following extracting information and conducting a methodological quality evaluation for study inclusion based on inclusion and exclusion criteria, RevMan 5.2 and Stata 12.0 software were used to perform a meta-analysis and the Jadad scale was used for evaluation of study quality. A total of 9 RCTs and 4,681 patients were included in this meta-analysis. The comparison between docetaxel-based therapy with and without antiangiogenic agents revealed no statistically significant differences regarding prostate-specific antigen response rate [risk ratio (RR)=0.99, 95% confidence interval (CI): 0.87–1.12, P=0.84], overall survival (OS) [hazard ratio (HR)=0.97, 95%CI: 0.91–1.05)] and progression-free survival (PFS) (HR=0.99, 95%CI: 0.83–1.18); however, the incidence of treatment-related mortality was higher in the docetaxel-based therapy with antiangiogenic agents group (RR=1.95, 95%CI: 1.23–3.11, P=0.005), whereas the incidence of thrombus formation was higher in the docetaxel-based therapy without antiangiogenic agents group (RR=0.57, 95%CI: 0.41–0.80, P=0.001). In conclusion, our findings indicated that docetaxel combined with antiangiogenic agents did not increase the OS or the PFS of the patients with castration-resistant prostate cancer, whereas it may increase the risk of treatment-related mortality. However, further RCTs with larger, high-quality patient samples are required to verify these findings.