You're looking at the wrong numbers and the wrong studies.
Here's a review of RTOG 96-01 that may make more sense to you (about
halfway down the page):Anti-androgen therapy enhances outcomes of salvage radiation
They are the wrong numbers because you're looking at "overall survival" rather than "prostate cancer survival." The antiandrogens reduced death from prostate cancer at last follow-up from 7.5% to 2.3% and it also cut the incidence of metastases from 23% to 14%. These numbers are low because the disease is slow-moving and the length of follow-up was 12.6 years. Overall mortality reflects deaths from any
It is the wrong study because RTOG 96-01 only looked at the use of an anti-androgen (bicalutamide), whereas the standard of care nowadays is androgen deprivation therapy - ADT (e.g., Lupron). A more relevant study is GETUG-AFU 16. After 5 years, progression-free survival was already significantly better with ADT - 80% vs. 62% without ADT.Combining ADT and salvage radiation therapy improves outcomes
You might want to share those with your RO.