Adding antiandrogen therapy with bicalutamide to salvage radiotherapy significantly improved long-term survival and reduced the risk of metastatic disease compared with radiation treatment alone in patients with recurrent prostate cancer, a study published in The New England Journal of Medicine has shown.1
Many men with prostate cancer who have undergone radical prostatectomy and have evidence of disease recurrence require salvage radiation treatment; however, it is unclear whether adding antiandrogen therapy to radiotherapy will enhance cancer control and improve overall survival.
To evaluate the impact of antiandrogen therapy with salvage radiation therapy, researchers enrolled 760 patients with T2 or T3 disease, no nodal involvement, and a detectable PSA level of 0.2 to 4.0 ng/mL who had undergone prostatectomy with a lymphadenectomy.
For the double-blind, phase 3 trial (ClinicalTrials.gov Identifier: NCT00002874), investigators randomly assigned the patients to undergo radiotherapy with either daily bicalutamide for 24 months or placebo after radiation.
After a median follow-up of 13 years, 76.3% of patients in the bicalutamide group were alive at 12 years compared with 71.3% of those in placebo group, corresponding to a 23% reduction in the risk of death with antiandrogen therapy vs placebo (hazard ratio, 0.77; 95% CI, 0.59-0.99; P =.04).
Investigators found that significantly more patients in the placebo arm had died by year 12 than in the bicalutamide arm (13.4% vs 5.8%; P <.001) and significantly fewer patients who received multimodality therapy developed metastatic disease at 12 years (14.5% vs 23.0%; P =.005).
The incidence of late radiation-related adverse events was similar between the 2 treatment arms; however, significantly more patients in the bicalutamide arm developed gynecomastia (69.7% vs 10.9%; P <.001).
The findings ultimately suggest that adding antiandrogen therapy to salvage radiotherapy reduces the risk of all-cause death, prostate cancer-related death, and metastasis in patients with recurrent disease after radical prostatectomy.
1. Shipley WU, Seiferheld W, Lukka HR, et al. Radiation with or without antiandrogen therapy in recurrent prostate cancer. N Engl J Med. 2017;376(5):417-428.