A lung nodule was found almost 3 years ago that was believed to be malignant since it showed up as spiculated on the CT scan, the size was 1.4 x 1.0 cm. We believed it was in cell cycle arrest due to the fact it was also found on a prior CT a year prior when checking past CT scans, but was missed at that time, it was the sameo, 1.4 x 1.0 cm. We have done periodic scans every 3-6 months and it has remained exactly the same size. On the current CT done a few weeks ago the size measured 1.4 x 1.1 cm, a 0.1 cm increase. All my scans have been done at the same location, on the same machine and interpreted by the same radiologist to allow consistent results////. My question, is the 0.1 change a forebearer of things to come or just some sort of error due to some variable? The nodule has not been ttouched in any way, I never allowed them to do a biopsy, but a PET scan was done about a year ago, which was dimly lit showing very little activity, I think it came up as a 5, with the background was a 4. Is it possible the periodic CT scans and PET can cause growth to begin, I have been doing low dose CT, 1.5 mSv, not sure what the PET was. Thank you.