I had a 13mm nodule show up in my lower right lung on a chest x-ray in 2007, and a follow-up CT diagnosed it to be a benign granuloma. It still shows up on imagining but has not changed in size or appearance since it first appeared. I've since had a series of low-dose CT screenings that haven't turned up anything new either.
As an update, the last low dose CT (LDCT) screening I had performed on 12/7 indicated a previously undetected 5 mm module in the lower right lobe, not specifically characterized. The radiologist recommended a follow up LDCT in three months, which of course I will do. That's exactly why I do these, to pick up anything suspicious while still early.