I'm guessing your Dad had a stage II cancer? With a 30% chance of recurrence without radiation that would fit from what I was told. But only 5% with radiation actually sounds pretty low.

Anyway, the deal with radiation is that it's the cumulative effect of it that kills the cancer cells so doing it halfway doesn't get you half the benefits of doing it all the way. It's basically not much better than having not done it at all. I think if there's any way you can, you should encourage your Dad to stick out the treatment. He'll probably be glad he did after it's over and although he is getting up there in years, a death from this form of cancer is still not the way I'd prefer to go.

I agree with Gary that you should get his pain and nutrition under control, anyway before letting him give up. Like Gary, I tend to want to be sure elderly people don't give up too quickly although ultimately it is his right to choose to quit. My grandfather lived through a heart valve replacement (open heart surgery where they cool you down and stop your heart for a while) at age 82 and it kept him going until age 98--and they were 16 good years for him.

Nelie