Short-term androgen deprivation therapy (STADT) in combination with radiotherapy (RT) in men with intermediate-risk prostate cancer is associated with superior outcomes compared with dose-escalated RT alone, according to study data presented at the American Society of Clinical Oncology annual meeting in Chicago.
The study, by Abdenour Nabid, MD, of Centre Hospitalier Universitaire de Sherbrooke in Sherbrooke, Quebec, Canada, and colleagues included 600 men with intermediate-risk prostate cancer (IRPC) who were randomized to 6 months of STADT and 2 levels of prostate RT doses of 70 (arm 1) or 76 Gy (arm 2) or prostate dose-escalated RT alone at 76 Gy (arm 3). Subjects had a median age of 71 years, median PSA level of 10 ng/mL, and median Gleason score of 7. Patient characteristics were well balanced among the 3 arms, the investigators stated.
At a median follow-up of 6.5 years, biochemical failure occurred in 96 patients (16%). The failure rates were 13.5%, 11%, and 23.5% in arms 1, 2, and 3, respectively. The differences between arms 1 and 3 and arms 2 and 3 were statistically significant, but the differences between arms 1 and 2 were not, according to the investigators. The 5- and 10-year disease-free survival (DFS) rates for arms 1, 2, and 3 were 92.8%, 97.1%, and 85.5%, respectively, and 78.4%, 78.3%, and 65.9%, respectively. The differences in 5- and 10-year DFS rates between arms 1 and 3 and arms 2 and 3 were statistically significant, but the differences between arms 1 and 2 were not. The researchers found no significant differences among the 3 arms with respect to overall survival.