Ironically I am in the middle of being diagnosed with something that is a result of the Cranial radiation and some of the chemo I took (not sure specific drugs, they said they were "alkalines").
Apparently my Hypothalamus was partially damaged - and my Endocrine system has not been functioning as it should. I was diagnosed about 7 years ago with Hypothyroidism, but apparently there were other things that my GP wasn't looking for that weren't working correctly either.
I see the Endocrinologist again in a few weeks so I'll know more then.
Otherwise, as far as I know, there aren't any other major issues. My radiation was in 1986, so it's been a few years. I had 10 or 12 rads (I can't remember for sure). I do have a few issues with minor short term memory loss - but I made it through high school (5th in my class) and college (made Dean's list a couple of times) so it's not too bad.
If I had a choice to go back and choose whether or not to have radiation, I would still choose to have it. I'm still here today!!