[1] Aichi Canc Ctr Hosp, Dept Gastroenterol, Nagoya, Aichi 464, Japan
[2] Aichi Canc Ctr Hosp, Dept Endoscopy, Nagoya, Aichi 464, Japan
[3] Aichi Canc Ctr Hosp, Dept Gastrointestinal Surg, Nagoya, Aichi 464, Japan
[4] Kanazawa Univ, Innovat Clin Res Ctr, Dept Biomed Stat, Kanazawa, Ishikawa, Japan
[5] Kumamoto Univ, Dept Gastroenterol & Hepatol, Kumamoto, Japan