1. Department of Urology, Teikyo University Chiba Medical Center, Ichihara, Chiba 299‑0111, Japan
2. Department of Pathology, Teikyo University Chiba Medical Center, Ichihara, Chiba 299‑0111, Japan
3. Department of Urology, Chiba University Graduate School of Medicine, Chiba, Chiba 260‑8677, Japan