1. Department of Medical Oncology, Affiliated Hui Zhou Municipal Central Hospital & Training Base for Masters of Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Huicheng District, Huizhou, Guangdong 516000, P. R. China
2. Department of Medical Oncology, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong 510000, P.R. China
3. Department of Pathology, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong 510000, P.R. China
4. Department of Radiotherapy, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong 510000, P.R. China