title: Current State of and Problems Related to Cancer of the Intestinal Tract Associated with Crohn's Disease in Japan.
abstract: OBJECTIVE
  Cancer of the intestinal tract (small and large intestine) associated with Crohn's disease has a low incidence but can be fatal if it develops. Thus, the key question is how to deal with this type of cancer. The current study surveyed major medical facilities that treat inflammatory bowel disease (IBD) surgically in Japan in order to examine the clinical features of cancer of the intestinal tract associated with Crohn's disease and explore ways to deal with this cancer in the future.
  
  
  METHODS
  Sixteen major medical facilities that treat IBD surgically were surveyed regarding cancer of the intestinal tract associated with Crohn's disease. The medical facilities had treated 3,454 patients with Crohn's disease, 122 of whom had developed intestinal cancer. The medical facilities were surveyed regarding those 122 patients.
  
  
  RESULTS
  The incidence of intestinal cancer associated with Crohn's disease has increased yearly. Cancer most often developed in the left side of the colon and, particularly, in the rectum and anal canal. Seventy-six percent of cases were diagnosed preoperatively, 4% were diagnosed intraoperatively, while the remaining 20% were diagnosed pathologically after surgery. The most prevalent histological type of cancer was mucinous carcinoma (50%). Forty-two percent of cancers were differentiated, with 4% being poorly differentiated. The surgical procedure performed most often (67%) was abdominoperineal resection. The 5-year survival rate by stage was 88% for Stage I, 68% for Stage II, 71% for Stage IIIa, 25% for Stage IIIb and 0% for Stage IV. Overall, the 5-year survival rate was 52%.
  
  
  CONCLUSIONS
  Gastrointestinal (GI) cancer associated with Crohn's disease had an incidence of 3.5%, but also involved a poor prognosis with a 5-year survival rate of 52%. Early detection through surveillance is crucial to improving the prognosis for patients. However, surveillance of the intestinal tract with endoscopy or contrast studies is technically and diagnostically hampered by Crohn's disease and intestinal strictures. A biopsy of the anal canal, a common site of cancer, can readily be performed and constitutes the first step in surveillance.
authors.affiliation: Department of Surgery, Fukuoka University Chikushi Hospital, Chikusino, Japan daijiro@fukuoka-u.ac.jp.
authors.forename: Daijiro
authors.initials: D
authors.lastname: Higashi
authors.affiliation: Department of Surgery, Fujita Health University, Toyoake, Japan.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Katsuno
authors.affiliation: Inflammatory Bowel Disease Center, Yokohama City University Medical Center, Yokohama, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kimura
authors.affiliation: Coloproctology Center, Tohoku Rosai Hospital, Sendai, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Department of Inflammatory Bowel Disease Surgery, Hyogo College of Medicine, Nishonomiya, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ikeuchi
authors.affiliation: Advanced Surgery Center Sapporo Higashi Tokushukai Hospital, Sapporo, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Kono
authors.affiliation: Department of Surgery, Nishinomiya Municipal Central Hospital, Nishinomiya, Japan.
authors.forename: Riichiro
authors.initials: R
authors.lastname: Nezu
authors.affiliation: Division of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Hatakeyama
authors.affiliation: Division of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kameyama
authors.affiliation: Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Iwao
authors.initials: I
authors.lastname: Sasaki
authors.affiliation: Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Kouhei
authors.initials: K
authors.lastname: Fukushima
authors.affiliation: Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Gastrointestinal and Pediatric Surgery, Mie University Graduate School of Medicine, Tsu, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Kusunoki
authors.affiliation: Department of Gastrointestinal and Pediatric Surgery, Mie University Graduate School of Medicine, Tsu, Japan.
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Araki
authors.affiliation: Department of Surgical Oncology, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Maeda
authors.affiliation: Department of Surgery 2, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Kameoka
authors.affiliation: Department of Surgery 2, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Itabashi
authors.affiliation: Department of Surgery 2, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Sayumi
authors.initials: S
authors.lastname: Nakao
authors.affiliation: Department of Surgery, Fujita Health University, Toyoake, Japan.
authors.forename: Koutaro
authors.initials: K
authors.lastname: Maeda
authors.affiliation: Department of Surgery, Hiroshima University, Hiroshima, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ohge
authors.affiliation: Department of Surgery, Hiroshima University, Hiroshima, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Watadani
authors.affiliation: Department of Surgical Oncology and Vascular Surgery, The University of Tokyo, Tokyo, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Surgical Oncology and Vascular Surgery, The University of Tokyo, Tokyo, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Sunami
authors.affiliation: Department of Surgery, Junwakai Memorial Hospital, Miyazaki, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hotokezaka
authors.affiliation: Inflammatory Bowel Disease Center, Yokohama Municipal Citizen's Hospital, Yokohama, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Sugita
authors.affiliation: Coloproctology Center, Tohoku Rosai Hospital, Sendai, Japan Department of Surgery, Sendai Red Cross Hospital, Sendai, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Funayama
authors.affiliation: Department of Surgery, Fukuoka University Chikushi Hospital, Chikusino, Japan.
authors.forename: Kitaro
authors.initials: K
authors.lastname: Futami
mesh_terms: D003424:Crohn Disease / Q000453:epidemiology* / Q000473:pathology; D006801:Humans; D015994:Incidence; D007414:Intestinal Neoplasms / Q000401:mortality*; D007564:Japan / Q000453:epidemiology; D016019:Survival Analysis
keywords: Crohn's disease; cancer of the intestinal tract; surgical treatment