@ireland1964 Yes, there is proton SBRT (few sessions w/high doses). I did not choose Proton SBRT due to reported increased risk of urinary bother. (See Dr. Rossi’s comments on this topic at the PCRI 2023 Mid-Year Conference: starting around timestamp 4:30:45 at https://www.youtube.com/live/WTqPnSRYtW4)

If you want to watch his entire presentation, Dr. Rossi has a lot of information about proton radiation treatments in his portion of that conference Starting at about 3:38:45 at that same link.

IMRT (intensity modulated radiation therapy) is photon-based radiation therapy. It utilizes high-energy X-rays (photons).

IMPT (Intensity-Modulated Proton Therapy) uses protons (heavy charged particles). Think of "proton radiation" as the overall category of treatment, while IMPT is a specific, technique used to deliver it.

My proton radiation was delivered (in 28 sessions @ 2.5 grays of radiation per session) with a Varian ProBeam Proton Therapy system. It uses pencil-beam scanning, and is accurate and precise at depth-dose control, completely eliminating "exit dose" radiation behind the prostate.

I did not use Proxtox prior to treatment. There are a dozen different biomarker (genomic) tests as well as genetic (germline) testing that can be utilized depending on what information you’re looking for. In my case, I had the OncotypeDx and Prolaris tests as well as the Promise genetic (germline) test.