I am 55 years old and diagnosed with moderate COPD 5 years ago. I have given up smoking but I do vape. I was told 12 months ago that I had a 4mm nodule on my lung and it is now 7mm. I now have to have to have 6 monthly CT scans to keep an eye on it but was not given any further information? ie: what could it be? Why are they monitoring it etc? Has anyone else had this x