1. Department of Gastroenterology, Sapporo Kosei General Hospital, Japan
2. Department of Surgical Pathology, Sapporo Kosei General Hospital, Japan
3. Institute of Biomedical Research, Sapporo Higashi Tokushukai Hospital, Japan
4. Department of Surgery, Sapporo Kosei General Hospital, Japan
5. Department of Investigative Pathology, Tohoku University Graduate School of Medicine, Japan