1. Digestive Disease Center and Research Institute, Department of Internal Medicine, SoonChunHyang University School of Medicine, Bucheon, Korea (the Republic of)
2. Department of Pathology, SoonChunHyang University School of Medicine, Bucheon, Korea (the Republic of)
3. Department of Surgery, SoonChunHyang University School of Medicine, Bucheon, Korea (the Republic of)
4. Digestive Disease Center and Research Institute, Department of Internal Medicine, SoonChunHyang University School of Medicine, Cheonan, Korea (the Republic of)
5. Digestive Disease Center and Research Institute, Department of Internal Medicine, SoonChunHyang University School of Medicine, Seoul, Korea (the Republic of)