Before he starts on lifelong hormone therapy, it may be worth a final shot at detecting where that hidden reservoir of prostate cancer is, and possibly eliminating it with some SBRT. For some of the scans (like C11 Choline or Acetate PET), he would have to have a PSA of at least 2 before anything is likely to show up. Ideally, he wants to detect it now while his PSA is lower than that.
There's a new kind of PET scan that is in clinical trials right now that may be able to find where that cancer is hiding. It's called a 18F-DCFBC PET/CT. A couple of people on this board have enrolled in that trial. It's at NIH in Washington DC, and they pay for your travel costs if accepted. Below is the descript
ion, and the contact details. You can call to see if he'd qualify.
/clinicaltrials.gov/ct2/show/NCT02190279- Allen