I have locally advanced PCa and have lymph node involvement. I've been on the STAMPEDE trial control arm for the past 21 months. I have 12-weekly injections of Prostap (similar to Zoladex) at my GP surgery and have had 37 fractions (74 Gray) of RT over 7 and a bit weeks at the hospital where I'm monitored by the Stampede team. When I started Stampede I was given a 5 year schedule of appointments, intially 6-weekly, now 12-weekly and 6-monthly from the autumn.
Before joining Stampede I had several lengthy consultations on my condition and how Stampede might benefit me. I also ensured that I was going to receive IMRT radiotherapy which has fewer side effects and possibly a better outcome. I ensured that I was going to receive RT to both my prostate (curative intent) and affected lymph nodes (a lower level of RT to reduce the risk of damage to the bowel). I have only recently discovered that had I not joined Stampede I would not have been offered RT to my lymph nodes - I have now been told that this is only for trial patients. So, I obtained more than the standard treatment offered to patients who are not on the trial. I have also had the reassurance of regular consultations which provide plenty of time to discuss one's condition and treatment options. I'm even seen on time, every time!
To my mind joining Stampede, even the control group, is a no-brainer. I'd be delighted to hear what other treatments are available to locally advanced non-Stampede patients. Your brother would be free to leave Stampede at any time.
Also, trials are meant to benefit those who will face the ghastly experience PCa in the future, not just the patients on the trial. It's worth joining for their sakes!