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