Sandy,
this is probably just academic. If you find out great, if not, no matter. It is not like there are that many options available anyway. (i.e. the rad plan must be completed even if things get more miserable which they most likely will). Of the other hand it IS just temporary, knowing this made thing more palatable (pardon the pun) for me. On the practical side, you want to watch out for thrush, that can make things a lot more miserable.
The generation of neutrons is something they are discussing these days for IMRT, largely because of the higher energies that are available. Besides being damaging all by themselves neutrons can also make certain elements radioactive (Silver and Mercury of fillings). The silver isotopes are very short lived. (We did this experiment in a physics class in the 80's using paraffin as a moderator. Anyway for a patient these are probably second order processes and not important... still interesting though in an abstract sort of way.

M