Have you told your radiologist about the symptoms? I've had four lung nodules radiated in the last seven years and the last one was in 12/24 using the cyberknife. About a month later I started experiencing some serious wheezing and shortness of breath and learned I had radiation pneumonitis, which is fairly common. My radiologist has been emphasizing since she first treated me in 2018 that if I had any SOB to notify her immediately. This is the first time I've experienced it, and it was a little scary. I was put on prednisone temporarily with good results. I'm no longer on the steroid, but I had a CT this week and it looks like there's still some inflammation around the radiated nodule and I'm still a little SOB when climbing stairs. Talk to your radiologist, maybe he can prescribe a brief trial of prednisone to see if your labored breathing improves.