Sixteen RCTs were included in the review (n=11,040 men, range 91 to 1,554; one study provided two treatment arms).
Immediate androgen-deprivation therapy without local treatment was associated with statistically significant improvements in overall survival of 10% (HR 0.90, 95% CI 0.83 to 0.97; five studies, six treatment arms) and improvements in cancer-specific survival of 21% (HR 0.79, 95% CI 0.71 to 0.89; five studies, six treatment arms) compared with delayed (deferred) androgen-deprivation therapy. Heterogeneity (Ι²) was not reported.
Adjuvant androgen-deprivation therapy was associated with a reduction in the risk of death of 31% (HR 0.69, 95% CI, 0.61 to 0.79; five studies; Ι²=10%) and in prostate cancer death of 49% (HR 0.51, 95% CI, 0.41 to 0.63; five studies; Ι²=59%) compared with local treatment alone.
Similar results were shown when restricted to the studies involving radiation as primary treatment.