Fatigue is the primary issue related to radiation therapy. Radiation starts in small doses and increases over the course of the treatment so expect him to get more fatigued as he gets further into his therapy. If he has hair he will start to lose it about three weeks into therapy. Hair loss is caused by the radiation, not chemo. He will not be completely bald since the radiation is targeted and will therefore have patches of hair that remain. His hair will start to return four to six months after ceasing radiation. Most patients have no, to little, effects from the Temodar.
Radiation effects older people much more than younger people so expect him to sleep a lot and not have much stamina. Long walks or rides in the car, going to an all day event (fair or shopping), house work, yard work, etc, will all likely come to an end as the radiation progresses. Older patients do tend to have a higher risk for more major radiation effects such as confusion and memory loss as well, although many patients suffer with general confusion such as time of day, which day it is, and things of that nature.
His taste for food may change dramatically and many of the things he might have loved before he may not have a taste for. Vice-versa, foods that he stayed away from in the past he may now crave.
In general, the vast majority of patients get through radiation/chemo without many serious or long-term issues. His good health will give him a good edge and be a huge benefit. His radiation doctor should be able to give you a good description of potential issues and effects your husband may run into.