1. Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea
2. Korean Liver Cancer Study Group, Seoul, Korea
3. Department of Biostatistics & Medical Informatics, Yonsei University College of Medicine, Seoul, Korea
4. Department of Internal Medicine, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea