1. Department of Health Sciences Tohoku University Graduate School of Medicine Sendai Japan
2. Division of Cancer Epidemiology and Prevention Miyagi Cancer Center Research Institute Natori Japan
3. Center for Preventive Medicine Osaki Citizen Hospital Osaki Japan
4. Department of Gastroenterology Miyagi Cancer Center Hospital Natori Japan
5. Department of Surgery Miyagi Cancer Center Hospital Natori Japan
6. Department of Epidemiology and Public Health Kanazawa Medical University Kahoku Japan