1. State Key Laboratory of Oncology in Southern China; Department of Radiation Oncology; Cancer Center; Sun Yat-sen University; Guangzhou People's Republic of China
2. Department of Radiation Oncology; Sun Yat-sen Memorial Hospital; Sun Yat-sen University; Guangzhou People's Republic of China
3. Imaging Diagnosis and Interventional Center; State Key Laboratory of Oncology in Southern China; Sun Yat-sen University Cancer Center; Guangzhou People's Republic of China
4. Department of Medical Statistics and Epidemiology; State Key Laboratory of Oncology in Southern China; Sun Yat-sen University Cancer Center; Guangzhou People's Republic of China