1. Division of Gastroenterology and HepatologyDepartment of Internal MedicineKeio University School of MedicineTokyoJapan
2. Center for Preventive MedicineKeio University HospitalTokyoJapan
3. Division of Molecular and Cellular MedicineNational Cancer Center Research InstituteTokyoJapan
4. Fellowship Training CenterMedical Education CenterKeio University School of MedicineTokyoJapan
5. Department of PathologyKeio University School of MedicineTokyoJapan
6. Division of Molecular PathologyNational Cancer Center Research InstituteTokyoJapan