I had radiated damage to the lung that was on the treated side. Later I developed Pneumonitis in that same lung.

I had pneomonitis too

I have a scar on my lung due to radiation and as JennO said, I also get pneumonia and chest colds very frequently. WHen it is below freezing I make sure I wear a scarf under my coat and try to only breathe through my nose . It sucks, yes, but I think of the alternative.....

My friends mother did radiation years ago. she did get some slight damage to her lung and now gets pneumonia and other chest colds pretty frequently. She was just recently hospitalized for it and in addition was told that due to the radiation she has a paralyzed diaphragm.

so far so good radiation to left side 4 months ago