Radical prostatectomy patients who received 24 months of antiandrogen therapy with daily bicalutamide (Casodex) in addition to salvage radiation therapy had notably higher long-term overall survival rates and lower risk of metastasis and death from prostate cancer than those who received radiation therapy with placebo, according to a new study.
“Adding hormonal therapy to radiation after prostatectomy is practice changing. For the first time, we have identified a treatment—hormonal therapy—that can improve overall survival when combined with radiation for patients who have developed recurrent disease after radical prostatectomy,” said senior author Howard Sandler, MD, of the Samuel Oschin Comprehensive Cancer Institute at Cedars-Sinai, Los Angeles.
The findings were published in the New England Journal of Medicine (2017; 376:417-28).
The study of 761 patients at 17 medical institutions in the U.S. and Canada tracked subjects for a 12-year period after the men had participated in RTOG 9601, a randomized clinical trial looking at the combined treatment. Eligible subjects had undergone prostatectomy with lymphadenectomy and had a tumor stage of T2 or T3, with no nodal involvement. They had PSA levels of 0.2 ng/mL to 4.0 ng/mL, and subsequent treatment with radiation therapy and either 24 months of bicalutamide, 150 mg daily, or daily placebo tablets.
“The patients who were studied in the RTOG 9601 trial were standard patients seen in our clinics routinely: patients with detectable PSA after radical prostatectomy, who developed their first PSA rise about 1.5 years after surgery. Median PSA was 0.6 ng/mL and median age was 65 at the time of study entry,” Dr. Sandler said.