I'm sorry to hear about
a recurrence after so long. Salvage cryo and RP usually have lots of side effects, so I agree that salvage radiation may be a better option. I hope Epstein or Bostwick read your biopsy slides as the radiation affects the cellular architecture and you really want some expert eyes on this. As part of whatever kind of salvage you decide upon, you might want an mpMRI to look for signs of cancer in the prostate fossa and pelvic LNs, as well as to localize the place in the prostate for an intraprostatic boost.
SBRT can be used as salvage. Donald Fuller
in San Diego has been using it for that purpose.
Salvage HDR brachy is also a good option. I know Mack Roach III at UCSF has used it for salvage after LDR failure, and he uses salvage LDR brachy as well.
I imagine Jeff Demanes at UCLA has done a few salvages with HDR brachy, but I can't say that for a fact. Worth a call, though.
I'd prefer SBRT or HDR as salvage because of the possibility of dose painting to avoid excess dose to bladder and rectum and to help avoid urethral strictures. They might do a rectal hydrogel spacer too.
I haven't ever heard of proton as salvage - maybe call UFJacksonville or MD Anderson to inquire.
Please let us know as your inquiries progress.