title: Prevalence of colorectal cancer in patients with ulcerative colitis: A retrospective, monocenter study in China.
abstract: BACKGROUND
  Ulcerative colitis-associated colorectal cancer (UC-CRC) is a serious complication of UC. Data on the clinical characteristics of patients in China are scarce.
  
  
  OBJECTIVE
  We aimed to study the incidence, characteristics, treatment, and prognosis of CRC patients with a history of UC.
  
  
  METHODS
  We identified patients with UC and followed them until the first occurrence of cancer, death, or emigration in a single study center in China.
  
  
  RESULTS
  A total of 4 UC-associated CRC patients were identified among the 642 cases recorded from January 2000 to December 2012. The overall risk of cancer was 0.64%. The overall median duration of UC was 15.5 years (range 6-21 years) in patients with UC-associated CRC. Of these patients, 75% (3/4) were at an advanced stage when they were diagnosed. Longer disease duration and extensive colitis were identified as risk factors for developing CRC, and 5-aminosalicylic acid and steroid therapies were not identified as protective factors against UC-associated CRC.
  
  
  CONCLUSIONS
  Patients with UC are at an increased risk for CRC. However, the prevalence of CRC in China remains lower than that in the West.
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhang
authors.forename: Sumei
authors.initials: S
authors.lastname: Sha
authors.forename: Bin
authors.initials: B
authors.lastname: Xu
authors.forename: Shuhui
authors.initials: S
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, P. R. China.
authors.forename: Kaichun
authors.initials: K
authors.lastname: Wu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002681:China / Q000453:epidemiology; D003093:Colitis, Ulcerative / Q000150:complications* / Q000473:pathology; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult