I understand completely. I had the same fears as I have a nasty family history of pulmonary issues. Currently my lung tests and scan that I have had are very good. Before I even made the decision of which type of surgery to have, I had a conference call with my surgical oncologist and my lung doctor. My lung doctor , in practice for 40 years, has only seen 1 or 2 cases of radiation induced pulmonary fibrosis. But he and the surgical oncologist were citing much lower stats than I had read. I wasn't convinced. So, they arranged for a consultation with my radiation oncologist. We went over how the radiation is done and how she targets the tumor area while I am doing a deep inhalation breath hold. That technique helps move thelung out of the way a bit. At the consultation my radiation oncologist showed me the pictures of other patients and how little of the lung is at risk. I started my radiation on 1/30, 8 down - 7 to go. Following my 1st she showed me my pictures. The treatment she has designed for me the lungs are out of the target area. I was diagnosed with IDC stage 1A HR+HER2- tumor was 4mm with 8 mm clear margins and negative nodes. The tumor was so small that typing wasn't done as there might not been enough tissue to test. I urge you to talk with your radiation oncologist. Good luck.