1. Department of Oncology, Southwest Hospital, Third Military Medical University, Chongqing, People's Republic of China.
2. Department of Oncology, The General Hospital of Chongqing Iron and Steel Group, Chongqing, People's Republic of China.
3. Department of Radiology, Vanderbilt University Medical Center, Nashville, Tennessee.
4. Department of Internal Medicine, First Hospital of Dadukou District, Chongqing, People's Republic of China.
5. Department of Radiation Medicine, Chongqing Medical University, Chongqing, People's Republic of China.