[Xiao, Fangzhu; Xiao, FZ; Yao, Xiangrong] Univ South China, Sch Publ Hlth, Hengyang 421001, Hunan, Peoples R China.
[He, Junyan] Univ South China, Affiliated Hosp 1, Hengyang Med Sch, Dept Oncol Radiotherapy, Hengyang, Hunan, Peoples R China.
[Xiao, Wentao] Nantong Univ, Med Sch, Affiliated Hosp, Dept Radiat Oncol, Nantong, Jiangsu, Peoples R China.
[Chen, Limou] Xiangnan Univ, Sch Publ Hlth, Chenzhou, Hunan, Peoples R China.