1. Department of Gastroenterological Surgery, Aichi Cancer Centre, Nagoya, Japan
2. Gastric Surgery Division, National Cancer Centre Hospital, National Cancer Centre Research Institute, Tokyo, Japan
3. Cancer Information and Epidemiology Division, National Cancer Centre Research Institute, Tokyo, Japan
4. Department of Surgery, Niigata Cancer Centre Hospital, Niigata, Japan
5. National Shikoku Cancer Centre, Matsuyama, Japan