1. Department of Otolaryngology-Head and Neck Surgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
2. Department of Pathology, Xiangya Hospital, Central South University, Changsha, Hunan 410007, P.R. China
3. Department of Otolaryngology-Head and Neck Surgery, The Fifth Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830000, P.R. China