1. Department of Gastroenterology and Hepatology, Yokohama City University Graduate School of Medicine, Yokohama, Japan
2. Department of Palliative Medicine, International University Health and Welfare, Narita Hospital, Narita, Japan
3. Department of Internal Medicine, Asakura Hospital, Konan-ku, Yokohama, Japan
4. Department of Gastroenterology, National Hospital Organization Yokohama Medical Center, Totsuka-ku, Yokohama, Japan
5. Department of Gastroenterology, Shinyurigaoka General Hospital, Kawasaki, Japan
6. Department of Pharmacology, Shimane University Faculty of Medicine, Shimane, Japan
7. Department of Oncology, Yokohama City University Graduate School of Medicine, Yokohama, Japan