1. Department of Urology, Hebei Medical University, Shijiazhuang, P. R. China
2. Department of Urology, Songshan General Hospital, Chongqing, P. R. China
3. Department of Urology, the Second Affiliated Hospital, Army Medical University, Chongqing, P. R. China
4. Department of Urology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China