1. Department of Radiation Oncology; National Cancer Center/Cancer Hospital & Shenzhen Hospital; Shenzhen 518116 Guangdong P. R. China
2. Department of Radiation Oncology; The First Affiliated Hospital of Sun Yat-sen University; Guangzhou 510080 Guangdong P. R. China
3. State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center; Guangzhou 510060 Guangdong P. R. China
4. Department of Radiation Oncology, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center; Guangzhou 510060 Guangdong P. R. China
5. Department of Radiation Oncology; Cancer Hospital Affiliated to School of Medicine; Chengdu 610041 Sichuan P. R. China
6. Department of VIP Region; Sun Yat-sen University Cancer Center; Guangzhou 510060 Guangdong P. R. China