Re: Recurrent Prostate Cancer
What does your oncologist say? He's probably seen a lot of PSA patterns after SRT. I think it's a good sign that the cancer was still localized that you had a drop in PSA soon after the radiation treatment. So the increase might be a bounce. If it were me, I'd want to monitor that closely before taking a next step.
In case it turns out not to be a bounce... Before you start on lifelong hormone therapy, you might ask your doctor to take a shot at trying to find it. Traditional bone scans are useless when your PSA is so low. If you are willing to take a one-day trip to Rochester, MN, the Mayo Clinic offers an FDA-approved C-11 Choline PET/CT scan. I don't know what the cost is or if your insurance would cover it. They have been able to find sites of metastases that other kinds of imaging can't find. If they find just a few, you can have your radiologist zap them with some SBRT. That might cure you or at least slow things down.
If they can't find any sites, it could mean that there are micrometastases that are too small to be seen. In that case, hormone therapy is the standard of care. There are clinical trials you might want to look into that involve new kinds of hormone therapy, immune therapy, and chemotherapies earlier in the disease progression process.
But first things first -- you and your oncologist need to figure out if it's just a bounce.