1. Department of Gastroenterology, Rheumatology and Clinical Immunology, Sapporo Medical University School of Medicine, Sapporo, Japan
2. Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
3. Department of Gastroenterology, Teine Keijinkai Hospital, Sapporo, Japan
4. Department of Pathology, Teine Keijinkai Hospital, Sapporo, Japan
5. Department of Surgical Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
6. Department of Surgery, Surgical Oncology and Science, Sapporo Medical University School of Medicine, Sapporo, Japan
7. Department of Molecular Biology, Sapporo Medical University School of Medicine, Sapporo, Japan
8. The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
9. Department of Gastroenterology and Hepatology, St. Marianna University School of Medicine, Kawasaki, Japan