[1] Kanazawa Univ, Dept Surg Gastroenterol, Kanazawa, Ishikawa 9208641, Japan
[2] Toyama Prefectural Cent Hosp, Dept Surg, Toyama, Japan
[3] Publ Cent Hosp Matto Ishikawa, Dept Surg, Haku San, Japan
[4] Kanazawa Med Univ, Dept Gen & Digest Surg, Kahoku, Ishikawa 92002, Japan
[5] Univ Fukui, Dept Surg 1, Fukui 910, Japan
[6] Toyama Rosai Hosp, Dept Surg, Uozu, Toyama, Japan
[7] Takaoka City Hosp, Dept Surg, Takaoka, Toyama, Japan
[8] Toyama City Hosp, Dept Surg, Toyama, Japan
[9] Keiju Med Ctr, Dept Gastroenterol, Nanao, Japan
[10] Asanogawa Gen Hosp, Dept Surg, Kanazawa, Ishikawa, Japan
[11] NTT West Kanazawa Hosp, Dept Surg, Kanazawa, Ishikawa, Japan
[12] Kanazawa Social Insurance Hosp, Dept Surg, Kanazawa, Ishikawa, Japan
[13] Kurobe City Hosp, Dept Surg, Kurobe, Japan