1. Department of Surgery, National Defense Medical College, Tokorozawa, Saitama 359‑8513, Japan
2. Department of Surgery, Self‑Defense Forces Central Hospital, Setagaya, Tokyo 154‑8532, Japan
3. Department of Diagnostic Pathology, Self‑Defense Forces Central Hospital, Setagaya, Tokyo 154‑8532, Japan
4. Department of Pathology, National Defense Medical College, Tokorozawa, Saitama 359‑0042, Japan