[1] Mitsui Mem Hosp, Gastroenterol, Tokyo, Japan
[2] Japanese Red Cross Med Ctr, Gastroenterol, Tokyo, Japan
[3] Kanto Cent Hosp, Gastroenterol, Tokyo, Japan
[4] Shioda Hosp, Hepatol, Katsu Ura, Japan
[5] Kyoundo Hosp, Hepatogastroenterol, Tokyo, Japan
[6] Komagome Hosp, Tokyo Metropolitan Canc & Infect Dis Ctr, Gastroenterol, Tokyo, Japan
[7] JR Tokyo Gen Hosp, Gastroenterol, Tokyo, Japan
[8] Teikyo Univ, Chiba Med Ctr, Gastroenterol, Ichihara, Chiba, Japan