recently had a pet scan for what could have been a cancerous lung nodule. Came back negative (thank god), but report showed flattened diaphragm mild COPD. Just wondering if this result could be possibly inaccurate. I run 20 miles per week with no issues. Walk up 5 flights of stairs at work daily, with only mild fatigue. I was shocked to read this. I was a light smoker in my 20s and 30s and am now 45. Always been active and can outrun people half my age. Just confused. Thanks for listening. If this is accurate I want to of course try to keep this mild as long as possible.