Probable overdiagnosis. An 80 year old woman, former smoker, with a history of a left upper lobectomy for a stage I adenocarcinoma, has an 11 mm (arrow) ground glass opacity in the right upper lobe. The nodule has not changed in over 3-years and is currently being followed with annual CT. If this is a cancer it is likely to be an adenocarcinoma in situ and may represent and overdiagnosis cancer.