I am 74 and finished my 5 proton treatments at Mayo Phoenix in April. PSA 2.9 two cores of 4-3 and two of 3-out of 30 cores taken. The positive cores were all from the area of the 7 mm lesion that the MRI showed a Priads 4. The 30 cores were because of my 120-gram prostate. I have had no side effects and even messaged my radiation oncologist to ask if he was sure they gave me the right dose of radiation. The only way I could tell anything was done was two tan circles on each hip where the radiation entered. My three month follow up PSA was less than .1 which they said was undetectable. Needless to say, I am thrilled with the results. I just saw an article on the BBC app yesterday that said that a new study just released proved that the 5 radiation treatment is better than 20 or more of a lower dose.