1. National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China
2. Department of Epidemiology and Biostatistics School of Public Health, Xi'an Jiaotong University Health Science Center Xi'an Shaanxi China
3. Cixian Cancer Hospital/Cixian Institute for Cancer Prevention and Control Handan China
4. Linzhou Cancer Hospital Anyang China
5. Feicheng People's Hospital Taian China
6. Cancer Institute of Yangzhong City/People's Hospital of Yangzhong City Zhenjiang China
7. Yangcheng Cancer Hospital Jincheng China
8. Yanting Cancer Hospital Mianyang China