Proton has been used for treating various solid cancer tumors for quite a while. But, there are only 46 active cancer treatment centers in the U.S. (https://www.proton-therapy.org/map/) so, not as much proton is being done compared to photon.

As for side-effects —> Though recent studies (COMPPARE and PARTIQoL) investigating the effectiveness and impact on quality of life of proton vs photon therapy techniques for prostate cancer appear to be indicating statistically equivalent outcomes, the fact that proton has out-performed photon for other solid cancer tumors (with minimal collateral tissue damage) has left me with questions as to whether there are other factors - unaccounted for in the clinical studies - that are at play. The Laws of Physics are the same; the Bragg-Peak characteristics of proton are the same; theoretically, the outcomes should prefer proton.

My experience with proton quality-of-life side-effects —> I only had 1 day of adverse side-effects during my 28 sessions of proton radiation treatments (during April-May 2021). On the 3rd day of treatment, I had urinary issues. My RO told me that with some men there’s an inflammatory response to the radiation, and if that inflammation is near the urethra can cause the issues that I was experiencing. He recommended that I take 2 Tamsulosin/day for the remainder of the treatments. I took 2 that night and 2 the next morning, and then 2 daily from then on; everything cleared up by that next afternoon; I haven’t had any issues since. My “recovery” from proton radiation treatments has been quite uneventful.

I don’t use the word “cure.” With prostate cancer having about a 33% rate of recurrence, I can only say that I have “no evidence of disease.” (Ask me again after my 6-month PSA test on December 15th.). My PSA right before treatment was 7.976; PSA dropped as low as < 0.008 during treatment; my nadir was 0.198; my PSA now ranges between 0.350-0.550, my most recent PSA being 0.473 (which is “normal” for still having a prostate following radiation treatments).