1. Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea.
2. Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea.
3. Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
4. Cancer Research Institute, Seoul National University, Seoul, Korea.
5. Deparment of Radiology, Armed Forces Seoul Hospital, Seoul, Korea.
6. Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Korea.
7. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
8. Department of Thoracic Surgery, Seoul National University College of Medicine, Seoul, Korea.