StrataX is specially good to apply during treatment. It's so expensive due to all the research. The hospital had a code I used for a discount when ordering. You "feather" on a very light film and it protects from burning. Continuing using it for some weeks after radiation makes a difference too. Other creams are moisturisers. I keep what's left in the frig and used a dab for kitchen finger/hand burns and they disappeared.
I found some good info on scar massage here:- https://www.youtube.com/watch?v=oiDygSX2hM4