1. Department of Internal Medicine, Kyushu University Beppu Hospital, 4546 Tsurumihara, Tsurumi, Beppu 874-0838, Japan
2. Department of Hematology, Clinical Research Institute, NHO Kyushu Medical Center, Fukuoka 810-0065, Japan
3. Department of Hematology and Oncology Research, NHO Nagoya Medical Center, Nagoya 460-0001, Japan
4. Department of Hematology, NHO Shibukawa Medical Center, Shibukawa 377-0204, Japan
5. Department of Hematology, NHO Hiroshimanishi Medical Center, Otake 739-0696, Japan
6. Department of Hematology, NHO Sendai Medical Center, Sendai 983-8520, Japan
7. Department of Pathology, School of Medicine, Kurume University, Kurume 830-0011, Japan