1. Department of Surgery, The Jikei University School of Medicine, Tokyo, Japan.
2. Department of Surgery, Yamagata Prefectural Central Hospital, Yamagata, Japan.
3. Department of Digestive Surgery, Nihon University School of Medicine, Tokyo, Japan.
4. Department of Digestive Surgery, Imamura General Hospital, Kagoshima, Japan.
5. Department of Gastroenterology and Minimally Invasive Surgery, Juntendo University School of Medicine, Tokyo, Japan.
6. Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.
7. Department of Surgery, JCHO Sapporo Hokushin Hospital, Sapporo, Japan.
8. Mitsugi General Hospital, Hiroshima, Japan.
9. Faculty of Letters, Arts and Sciences, Waseda University, Tokyo, Japan.
10. Department of Laboratory Medicine, The Jikei University School of Medicine, Tokyo, Japan.