Efficacy and safety of combined androgen blockade with antiandrogen for advanced prostate cancer.

BACKGROUND

Combined androgen blockade (cab) is a promising treatment modality for prostate cancer (pca). In the present meta-analysis, we compared the efficacy and safety of first-line cab using an antiandrogen (aa) with castration monotherapy in patients with advanced pca.

METHODS

PubMed, embase, Cochrane, and Google Scholar were searched for randomized controlled trials (rcts) published through 12 December 2016. Hazard ratios (hrs) with 95% confidence intervals (cis) were determined for primary outcomes: overall survival (os) and progression-free survival (pfs). Subgroup analyses were performed for Western compared with Eastern patients and use of a nonsteroidal aa (nsaa) compared with a steroidal aa (saa).

RESULTS

Compared with castration monotherapy, cab using an aa was associated with significantly improved os ( = 14; hr: 0.90; 95% ci: 0.84 to 0.97; = 0.003) and pfs ( = 13; hr: 0.89; 95% ci: 0.80 to 1.00; = 0.04). No significant difference in os ( = 0.71) and pfs ( = 0.49) was observed between the Western and Eastern patients. Compared with castration monotherapy, cab using a nsaa was associated with significantly improved os (hr: 0.88; 95% ci: 0.82 to 0.95; = 0.0009) and pfs (hr: 0.85; 95% ci: 0.73 to 0.98; = 0.007)-a result that was not achieved with cab using a saa. The safety profiles of cab and monotherapy were similar in terms of adverse events, including hot flushes, impotence, and grade 3 or 4 events, with the exception of risk of diarrhea and liver dysfunction or elevation in liver enzymes, which were statistically greater with cab using an aa.

CONCLUSIONS

Compared with castration monotherapy, first-line cab therapy with an aa, especially a nsaa, resulted in significantly improved os and pfs, and had an acceptable safety profile in patients with advanced pca.