1. Y-S Hung (corresponding author) Division of Hematology-Oncology, Chang Gung Memorial Hospital, School of Medicine, Chang Gung University, No. 5, Fuxing Street, Guishan Township, Taoyuan County 333, Taiwan, Republic of China;
2. Division of Hematology-Oncology, Chang Gung Memorial Hospital, School of Medicine, Chang Gung University, Taoyuan, Taiwan, and Department of Internal Medicine, Saint Paul's Hospital, Taoyuan, Taiwan
3. Department of Internal Medicine, Saint Paul's Hospital, Taoyuan, Taiwan
4. Department of Nursing, Saint Paul's Hospital, Taoyuan, Taiwan