My husband had Proton therapy in 2009 in Jacksonville FL. He is in remission but after 8 yrs he started to have bladder issues. Bleeding is the most common side effect of Proton therapy and it could be rectal or bladder. He went through ablations and urinary retention many times. Mayo Clinic in Jax diagnosed him with Radiation Cystitis due to Prostate cancer treatment. He was recommended to have Hyperbaric Oxygen Treatment because the bleeding in the bladder was difficult to stop. He had 80 treatments and his bladder healed. It doesn’t mean he was “cured” from his diagnosis because he still has the bladder affected but he is not bleeding. He just drinks lots of water and doesn’t lift heavy stuff. His quality of life changed a lot after being diagnosed but he is taking one day at a time. The oncologists in Proton Institutes don’t mention it but it happens. Hope this helps.