The University of Osaka, Hamamatsu University, The University of Osaka - Department of Gastroenterological Surgery, Japanese Foundation for Cancer Research - Cancer Institute Hospital, Shizuoka Cancer Centre, Kindai University, Gifu University - Department of Tumor Pathology, National Cancer Center Hospital East, Saitama University - University International Medical Centre, Kanagawa Cancer Center, Yokohama City University, University of Tokyo, Kansai Rosai Hospital, Wakayama Medical University - Clinical Study Support Centre, Japanese Foundation for Cancer Research - Cancer Institute Hospital and Keio University - Department of Surgery