Survival and incidence of colorectal cancer in patients with ulcerative colitis in Funen county diagnosed between 1973 and 1993.

BACKGROUND

The aim of the study was to determine the death rate and the risk of developing colorectal cancer in patients with ulcerative colitis in Funen County.

METHODS

The medical records of 801 patients with ulcerative colitis diagnosed in 1973-93 in Funen County were scrutinized with regard to colectomy, survival, and colorectal cancer, and in 1998 a follow-up was carried out.

RESULTS

The patients were managed at nine different hospitals: one university hospital, one central hospital, and seven smaller hospitals. The mean age at diagnosis was 41 years, and the mean duration of disease was 10.11 years. Sixty-one per cent of the patients were classified as having proctosigmoiditis, 21% as having left-sided colitis, and 18% as having pancolitis. In 127 patients who underwent proctocolectomy during the study period lethal complications occurred in 8 cases: 5 of 110 in Odense University hospital and 3 of 17 in the other hospitals. One hundred and twenty patients in the cohort died during the period of observation, nine of them of colitis-related causes. There was a slightly increased risk of early death in the cohort after 15 years of disease. Six colorectal cancers were found, whereas four were expected, giving a standard incidence ratio of 1.665. The cumulative cancer risk after 20 years' disease duration was 5.3% in the observed group, contrasting with an expected rate of 0.49%, and 10.1% after 25 years.

CONCLUSION

In this cohort of ulcerative colitis patients the mortality and the risk of developing colorectal cancer were slightly higher than expected compared with the background population.