A wide-scale Swedish study was carried out on 7,607 patients with IBD, diagnosed between 1954 and 1989; it included 3,936 men and 3,671 women. These patients were followed up and the incidence of colorectal cancers was determined between 1960 and 2004. This study demonstrated that men with IBD had a 60% higher risk of developing colorectal cancer than women. This supplementary risk was detected starting 10 years after evolution of the disease. Compared to the general population, the risk of developing colorectal cancer was 160% in men with IBD and 90% in women.

This study reinforces the importance of regular follow-up of patients with IBD, especially men. Moreover, it suggests that estrogens could have a protective effect against colorectal cancer associated with IBD.

Reference:

Söderlund S, Granath F, Broström O, Karlén P, Löfberg R, Ekbom A, Askling J. Inflammatory bowel disease confers a lower risk of colorectal cancer to females than to males. Gastroenterology. 2010 Feb 15. [Epub ahead of print]