I had 28 treatments of photon/IMRT and have significant side effects with urination and bowel movements 7+ months later. If I had done my homework I should have found somewhere to go for proton/IMPT treatments because of this data. Protons have unique physical properties, allowing for even better dose sparing to surrounding healthy tissues, especially for cancers in the head and neck.
The comparison between IMPT and IMRT often highlights IMPT's potential for reduced toxicity and improved quality of life. My quality of life has suffered as I need to be by a bathroom every 2 hours when drinking liquids and it burns when I go. My bowel movements are 3 times a day now with lots of gas. The oncologist that did my treatment plan really fried my insides. My PSA has already dramatically dropped so I am convinced what he did was overkill. The oncologist I see now said he is very surprised how fast it went down. Anyway, Good Luck with your treatments.