1. 1Departments of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
2. 2Departments of Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
3. 3Departments of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
4. 4Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea