1. Division of Research and Development for Minimally Invasive Treatment Cancer Center Keio University School of Medicine TokyoJapan
2. Department of Gastroenterology and Hepatology National Hospital Organization Tokyo Medical Center TokyoJapan
3. Endoscopy Division National Cancer Center Hospital TokyoJapan
4. Department of Gastroenterology Toranomon Hospital TokyoJapan
5. Division of Gastroenterology and Hepatology St. Marianna University School of Medicine KanagawaJapan
6. Department of Gastroenterology and Hepatology Gunma University Gunma Japan
7. Department of GastroenterologyTokyoJapan
8. Department ofEndoscopy and Endoscopic Surgery The University of Tokyo Tokyo Japan