well saliva glands to get nuked quite nicely during treatment but they also tend to recover... why don't they just remove the darn thing if it is not needed? too bad he's suffering - the rads won't be easy either but he will get through it. Try to stay on top of the pain. I'm not a big one for pain meds... but if they are needed then he should take it when he begins to feel it coming on... not when it is really hurting. If nothing helps he needs a consult to find something that does.

Hugs to you.