1. Institute of Urology, Lanzhou University Second Hospital, Key Laboratory of Urological Diseases in Gansu Province, Gansu Nephro-Urological Clinical Center, Lanzhou 730030, Gansu, China
2. Department of Pathology, Lanzhou University Second Hospital, Lanzhou, China
3. Department of Urology, University of Texas Health Science Center San Antonio, San Antonio, TX, USA