Natural history of pure ground-glass opacity lung nodules detected by low-dose CT scan.
BACKGROUND
Although focal ground-glass opacity (GGO) lung nodules are generally reported to grow slowly, their natural course is unclear. The purpose of this study was to elucidate the natural course of screening-detected pure GGO lung nodules in patients with no history of malignancy.


METHODS
We retrospectively reviewed the database of subjects who had undergone screenings involving low-dose CT scans. We included patients with pure GGO lung nodules who were followed for > 2 years after the initial screening.


RESULTS
Between June 1997 and September 2006, 122 pure GGO nodules were found in 89 patients. The median nodule size was 5.5 mm (range, 3-20 mm) in the largest diameter on initial low-dose CT scan. The median follow-up period per patient was 59 months. On a per-person basis, the frequency of growth was 13.5% (12 of 89 patients). On a per-nodule basis, the frequency of growth was 9.8% (12 of 122 nodules). Nodule growth was significantly associated with initial size and new development of an internal solid portion. The median volume doubling time was 769 days for growing pure GGO nodules. A total of 11 growing nodules were surgically validated, and all lesions were confirmed as primary lung cancer.


CONCLUSIONS
About 90% of the screening-detected pure GGO lung nodules did not grow during long-term follow-up in subjects with no history of malignancy and most growing nodules had an indolent clinical course. A strategy of long-term follow-up and selective surgery for growing nodules should be considered for pure GGO lung nodules.
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Seoul, South Korea.
Boksoon
B
Chang
Center for Health Promotion, Seoul, South Korea.
Jung Hye
JH
Hwang
Center for Health Promotion, Seoul, South Korea.
Yoon-Ho
YH
Choi
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Seoul, South Korea.
Man Pyo
MP
Chung
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Seoul, South Korea.
Hojoong
H
Kim
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Seoul, South Korea.
O Jung
OJ
Kwon
Department of Radiology and Center for Imaging Science, Seoul, South Korea.
Ho Yun
HY
Lee
Department of Radiology and Center for Imaging Science, Seoul, South Korea.
Kyung Soo
KS
Lee
Department of Thoracic Surgery, Seoul, South Korea.
Young Mog
YM
Shim
Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Joungho
J
Han
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Seoul, South Korea. Electronic address: sangwonum@skku.edu.
Sang-Won
SW
Um
D000328:Adult; D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008171:Lung Diseases / Q000000981:diagnostic imaging*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D055613:Multiple Pulmonary Nodules / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed