1. Palliative Care Center, Yonsei Cancer Center, Seoul, Republic of Korea.
2. Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea.
3. Yonsei Graduate School, Yonsei University College of Medicine, Seoul, Republic of Korea.
4. Division of Hematology and Oncology, Department of Internal Medicine, Sejong Chungnam National University Hospital, Sejong, Republic of Korea.
5. Division of Hematology and Oncology, Department of Internal Medicine, Chungnam National University College of Medicine, Daejeon, Republic of Korea.
6. Daejeon Regional Cancer Center, Daejeon, Republic of Korea.
7. Division of Medical Oncology, Department of International Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.