1. Radiotherapy Department, The Third Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530000, P.R. China
2. Department of Gastroenterology, The Third Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530000, P.R. China
3. Ear, Nose and Throat and Head and Neck Surgery Department, The Third Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530000, P.R. China