[A case of a pure ground glass opacity changing into advanced lung cancer confirmed by computed tomography]

We report a case of a ground glass opacity (GGO) transforming into advanced lung cancer, which we followed chronologically by CT. On November 2001, a chest CT was performed due to chest pain. Due to incidental discovery of a GGO of 11mm in the left S6, we decided to monitor its course with CT. At the time, the patient did not have respiratory symptoms, and his tumor markers were within normal limits. In a CT conducted on September 2003, a slight enlargement of the GGO as well as an increased density within it was observed. At that point, the patient refused an exploratory thoracotomy. On October 2006, a chest CT was conducted due to the possibility of pneumonia. At that time, the GGO found in the past CT had become a solid nodule. In addition, enlargement of the hilar and mediastinal lymph nodes were observed, based on which we made a diagnosis of advanced lung cancer.