Published online Mar 28, 2015. doi: 10.3748/wjg.v21.i12.3644
Peer-review started: September 1, 2014
First decision: September 27, 2014
Revised: October 11, 2014
Accepted: January 8, 2015
Article in press: January 8, 2015
Published online: March 28, 2015
AIM: To determine the incidence and risk factors for colorectal cancer (CRC) in patients with ulcerative colitis from a low prevalence region for CRC.
METHODS: Our prospective database yielded a cohort of 430 patients [age: 44 ± 14.6 years; 248 men (57.7%)] with ulcerative colitis (median disease duration 6, range: 1-39 years) for analysis. Of these, 131 (30.5%) had left-sided colitis and 159 (37%) extensive colitis. Patients with histologically confirmed CRC within the segment with colitis were compared with those without CRC, to determine the risk factors for the development of CRC.
RESULTS: Twelve patients (2.8%) developed CRC. The overall incidence density was 3.56/1000 patient-years of disease - 3/1000 in the first 10 years, 3.3/1000 at 10 to 20 years, and 7/1000 at > 20 years. Three of our 12 patients developed CRC within 8 years of disease onset. On univariate analysis, extensive colitis, longer duration of disease, and poor control of disease were associated with development of CRC. On multivariate analysis, duration of disease and extent of colitis remained significant.
CONCLUSION: CRC occurred in 2.8% of patients with ulcerative colitis in our population - an incidence density similar to that in Western countries in spite of a low overall prevalence of colon cancer in our population. The risk increased with extent and duration of disease.
Core tip: From an area with low prevalence of colon cancer, the risk of colorectal cancer (CRC) in patients with ulcerative colitis was as high as in those with high risk of CRC. Some patients developed CRC before the recommended commencement of colonoscopic surveillance for CRC.