1. Division of Community Health; Tohoku University Graduate School of Medicine; 2-1 Seiryo-machi Aoba-ku, Sendai Miyagi Japan
2. Division of Cancer Epidemiology and Prevention; Miyagi Cancer Center Research Institute; 47-1 Nodayama Medeshima-Shiode, Natori Miyagi Japan
3. Department of Surgical Oncology; Tohoku University Graduate School of Medicine; 1-1 Seiryo-machi Aoba-ku, Sendai Japan
4. Department of Surgery; Miyagi Cancer Center Hospital; 47-1 Nodayama Medeshima-Shiode, Natori Miyagi Japan
5. Department of Gastroenterology; Miyagi Cancer Center Hospital; 47-1 Nodayama Medeshima-Shiode, Natori Miyagi Japan