[1] Hakodate Municipal Hosp, Dept Gastroenterol, Hakodate, Hokkaido, Japan
[2] Hokkaido Univ Hosp, Dept Gastroenterol & Hepatol, Sapporo, Hokkaido, Japan
[3] Hokkaido Univ Hosp, Div Canc Ctr, Sapporo, Hokkaido, Japan
[4] Kushiro Rosai Hosp, Dept Med Oncol, Kushiro, Hokkaido, Japan
[5] Keiyukai Sapporo Hosp, Dept Med Oncol, Sapporo, Hokkaido, Japan
[6] Univ Toyama, Dept Gastroenterol & Hematol, Fac Med, Toyama, Japan
[7] Kouseiren Takaoka Hosp, Dept Gastroenterol, Takaoka, Toyama, Japan
[8] Niigata City Gen Hosp, Dept Gastroenterol, Niigata, Japan
[9] Oji Gen Hosp, Dept Gastroenterol, Tomakomai, Japan
[10] Teine Keijinkai Hosp, Dept Med Oncol, Sapporo, Hokkaido, Japan
[11] Sapporo Higashi Tokushukai Hosp, Dept Gastroenterol, Sapporo, Hokkaido, Japan
[12] Wakkanai City Hosp, Dept Internal Med, Wakkanai, Hokkaido, Japan
[13] Obihiro Kosei Hosp, Dept Gastroenterol, Obihiro, Hokkaido, Japan
[14] Hokkaido Gastroenterol Hosp, Dept Internal Med, Sapporo, Hokkaido, Japan
[15] Misawa City Hosp, Dept Internal Med, Misawa, Japan
[16] Nakadori Gen Hosp, Dept Surg Gastroenterol, Akita, Japan
[17] Tomakomai Nisshou Hosp, Dept Internal Med, Tomakomai, Japan
[18] Sapporo Hokuyu Hosp, Dept Gastroenterol, Sapporo, Hokkaido, Japan
[19] HGCSG, Data Ctr, Sapporo, Hokkaido, Japan
[20] Misawa City Hosp, Misawa, Japan
[21] Hokkaido Univ Hosp, Div Canc Ctr, Digest Internal Med, Sapporo, Hokkaido, Japan