I’m being treated now- 15 sessions, 5 days a week, proton beam radiation at Mayo. 3 down and so far so good. I’m using Mepitel film to help prevent radiation burn and skin sensitivity. I learned about it on this forum. The research looks encouraging so I thought I’d try it. Out of pocket expense, but cost is not prohibitive. Good luck!
https://store.mayoclinic.com/mepitel-film-dressing.html