1) Department of General Surgical Science, Graduate School of Medicine, Gunma University, Maebashi, Japan
2) Japanese Red Cross Maebashi Hospital, Maebashi, Japan
3) National Hospital Organization Takasaki General Medical Center, Takasaki, Japan
4) National Hospital Organization Shibukawa Medical Center, Shibukawa, Japan
5) Fujioka General Hospital, Fujioka, Japan
6) Public Tomioka General Hospital, Tomioka, Japan
7) Isesaki Municipal Hospital, Isesaki, Japan
8) Kiryu Kosei General Hospital, Kiryu, Japan
9) Gastroenterological Surgery, Gunma Prefectural Cancer Center, Ota, Japan
10) Saiseikai Maebashi Hospital, Maebashi, Japan
11) Japan Community Health Care Organization Gunma Chuo Hospital, Maebashi, Japan
12) Hidaka Hospital, Takasaki, Japan
13) Japanese Red Cross, Haramachi Hospital, Agatuma, Japan
14) Department of Surgery, National Hospital Organization Numata National Hospital, Numata, Japan
15) Tone Chuo Hospital, Numata, Japan
16) Ota Memorial Hospital, Ota, Japan
17) Tatebayashi Kosei General Hospital, Tatebayashi, Japan
18) Department of Public Health, Gunma University Graduate School of Medicine, Maebashi, Japan

Ken Shirabe¹⁾, Hiroshi Saeki¹⁾, Tatsuya Miyazaki²⁾, Tetsushi Ogawa³⁾, Fujio Makita⁴⁾, Yoshinori Shitara⁵⁾, Masami Machida⁶⁾, Naokuni Yasuda⁷⁾, Hiroyuki Kato⁸⁾, Hitoshi Ojima⁹⁾, Yasuo Hosouchi¹⁰⁾, Hiroshi Naito¹¹⁾, Hironori Tatsuki¹²⁾, Nobuyuki Uchida¹³⁾, Kotaro Iwanami¹⁴⁾, Takayuki Kohri¹⁵⁾, Kouji Hayashi¹⁶⁾, Shigeru Iwasaki¹⁷⁾, Hiroshi Koyama¹⁸⁾