1. Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
2. Department of Oncology, Asan Medical Center, University of Ulsan, Seoul, Korea.
3. Department of Internal Medicine, Chonnam National University Hwasun Hospital, Hwasun, Korea.
4. Hematologic Malignancy Branch, National Cancer Center, Ilsan, Korea.
5. Department of Internal Medicine, St. Mary Hospital, The Catholic University of Korea, Seoul, Korea.
6. Department of Internal Medicine, Seoul National University Hospiltal, Seoul, Korea.
7. Department of Internal Medicine, Gachon University Gil Medical Center, Incheon, Korea.