Colorectal cancer prevention in ulcerative colitis: a case-control study

Aliment Pharmacol Ther. 2000 Feb;14(2):145-53. doi: 10.1046/j.1365-2036.2000.00698.x.


Background: The risk of colorectal cancer (CRC) in ulcerative colitis (UC) increases with extent and duration of disease. Identifying other risk factors would allow targeting of sub-groups at greatest risk, enabling more cost-effective surveillance.

Methods: We conducted a case-control study comparing 102 cases of CRC in UC with matched controls. Odds ratios (OR) for cancer risk were estimated by conditional logistic regression. A multivariate model assessed the contribution of individual variables.

Results: Regular 5-aminosalicylic acid (5-ASA) therapy reduces cancer risk by 75% (OR 0.25, 95% CI: 0.13-0.48, P < 0.00001). Adjusting for other variables, taking mesalazine regularly reduces risk by 81% (OR 0.19, 95% CI: 0.06-0.61, P=0.006) and visiting a hospital doctor more than twice a year also reduces risk (OR 0.16, 95% CI: 0.04-0.60, P=0.007). Considering variables independently, having a family history of sporadic CRC in any relative increases risk fivefold (OR 5.0, 95% CI: 1.10-22.82, P < 0.04).

Conclusions: CRC risk among UC patients can be reduced by regular therapy with 5-ASA medication. Colonoscopic surveillance may be best targeted on those unable to take 5-ASAs (e.g. due to allergy) and those with a positive family history of CRC.

MeSH terms

  • Adolescent
  • Adult
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use
  • Case-Control Studies
  • Colitis, Ulcerative* / complications*
  • Colitis, Ulcerative* / drug therapy
  • Colorectal Neoplasms / etiology
  • Colorectal Neoplasms / prevention & control*
  • Female
  • Humans
  • Male
  • Mesalamine / therapeutic use*
  • Middle Aged
  • Multivariate Analysis
  • Odds Ratio
  • Regression Analysis
  • Risk Factors


  • Anti-Inflammatory Agents, Non-Steroidal
  • Mesalamine