1. Division of Urology, Niigata Rosai Hospital, Japan Organization of Occupational Health and Safety, Joetsu, Niigata 942‑8502, Japan
2. Division of Diagnostic Pathology, Niigata Rosai Hospital, Japan Organization of Occupational Health and Safety, Joetsu, Niigata 942‑8502, Japan
3. Department of Urology, Chiba University Graduate School of Medicine, Chiba, Chiba 260‑8670, Japan