1. Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
2. Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
3. Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul, Korea.
4. Department of Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.