1. Department of Gastroenterological Surgery, Toyonaka Municipal Hospital
2. Department of Gastroenterological Surgery, Osaka Rosai Hospital
3. Department of Gastroenterological Surgery, Ibaraki Prefectural Central Hospital
4. Department of Gastroenterological Surgery, Kindai Nara Hospital
5. Department of Surgery, Japan Community Health Care Organization Osaka Minato Central Hospital
6. Cancer Treatment Center, Toyonaka Municipal Hospital