I believe dandl48 is correct, SBRT is used for both Photon and Proton Radiation. Studies have yet to prove whether Proton is safer with fewer side effects than Photon. The thought is that Protons are delivered with a finer beam and this may reduce likelihood of radiation impacting non-prostate cells. Also, protons enter the prostate but do not exit... they only have an entrance path where as photons travel through the prostate and exit on the other side.

My last of 5 Proton treatments was Thursday 1/19/23. No major issues. Two days of prep, then 5 days of treatment. With the Holidays and a mild case of Covid the entire process took a bit longer than if it were done outside the Holiday Season and without the Covid.

Cannot say enough about the great people at Mayo Rochester. This is a national treasure. Rochester is known as Med-City and it is no wonder. Thousands of Doctors and many more staff. New buildings going up on Campus. Glad I made the investment to travel to Minnesota. Oregon, where I live does not have a Proton Beam facility and it did, it would still be a wise investment to make the trip to Minnesota. Out of towners can also find free lodging during treatment if needed. My wife and rented a house south of town and enjoyed a snowy Holiday Season.

Best wishes to all.