@dave56pa I had similar situation. Stage 1b NSCLC, three tumors treated with SBRT in two sessions over two years. I have severe COPD so surgery wasn’t an option. Both times I developed pneumonitis 4-5 weeks after treatment. The symptoms were very similar, short of breath, fatigue, and congestion. Only when I had my follow up CT at 90 days, were the docs able to determine that I had the pneumonitis resulting from the SBRT. They put me on a full dose (60MG) of prednisone and I had relief within two weeks. I was told @5% of SBRT patients get pneumonitis. You may want to follow up with your doc to see if it’s a reaction to the SBRT.