Colorectal cancer prevention in ulcerative colitis: a case-control study.
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.
Eaden
J
J
The Gastrointestinal Research Unit, Leicester General Hospital, Leicester, UK. jayne.a.eaden@btinternet.com
Abrams
K
K
Ekbom
A
A
Jackson
E
E
Mayberry
J
J
D000293:Adolescent; D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000150:complications* / Q000188:drug therapy; D015179:Colorectal Neoplasms / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008297:Male; D019804:Mesalamine / Q000627:therapeutic use*; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012044:Regression Analysis; D012307:Risk Factors
D000894:Anti-Inflammatory Agents, Non-Steroidal; D019804:Mesalamine