Ground-glass opacity lesions on computed tomography during postoperative surveillance for primary non-small cell lung cancer

Improvement in chest high-resolution computed tomography (CT) has increased the detection of ground-glass opacity (GGO) lesions. However, there is no clear therapeutic consensus about concurrent GGO lesions detected during postoperative follow-up chest CT after treatment for primary lung cancer. This study retrospectively and prospectively investigated 21 patients in whom 53 GGO lesions were detected during postoperative follow-up CT of non-small cell lung cancer at Kyushu University Hospital from April 2009 to February 2010. We investigated clinicopathological factors, such as age, gender, lesion number, size, laterality, time of identification, and enlargement or emergence of the inner solid component. The malignancy rate of the concurrent GGO lesions was assessed by log-rank test in the Kaplan-Meier curves. Twenty percent of the 53 GGO lesions had malignant radiological findings during the 5-year follow-up after they were first identified by CT. The newly emerging GGO lesions at postoperative CT had significantly more malignant radiological findings (39.5%) than other GGO lesions (9.5%). Three potentially malignant GGO lesions were treated by surgical resection and three were treated by stereotactic radiotherapy. These six treated GGO lesions showed a good clinical course without recurrence after treatment. Special attention should be paid to newly emerging GGO lesions after resection of primary non-small cell lung cancer. It is necessary to select an appropriate treatment, taking account of various factors such as the laterality and number of GGO lesions or the pathological stage of the postoperative lung cancer.