[1] Capital Med Univ, Beijing Shijitan Hosp, Dept Otorhinolaryngol Head & Neck Surg, 10 Yangfangdian Tieyi Rd, Beijing 100038, Peoples R China
[2] Capital Med Univ, Beijing Shijitan Hosp, Dept Pathol, Beijing 100038, Peoples R China
[3] Capital Med Univ, Beijing Shijitan Hosp, Dept Med Record Stat, Beijing 100038, Peoples R China
[4] Capital Med Univ, Beijing Chaoyang Hosp, Dept Thyroid & Neck Surg, Beijing 100020, Peoples R China