1. Department of Hematology, Sapporo Kiyota Hospital, Sapporo, Japan,
2. Department of Internal Medicine, Sapporo Kiyota Hospital, Sapporo, Japan,
3. Department of Surgery, Sapporo Kiyota Hospital, Sapporo, Japan,
4. Department of Pathology, Sapporo Medical University, Sapporo, Japan,
5. Department of Surgical Pathology, Sapporo Medical University, Sapporo, Japan,
6. Department of Hematology, Sapporo Medical University, Sapporo, Japan