Low incidence of colorectal dysplasia and cancer among patients with ulcerative colitis: A Turkish referral centre study

Objectives. To determine the incidences of dysplasia, adenomatous polyp and colon cancer in patients with ulcerative colitis (UC) and to evaluate the risk factors. Material and methods. We retrospectively reviewed the medical records of patients with UC admitted to the Turkiye Yuksek Ihtisas Hospital between 1994 and 2008 and who subsequently developed colorectal cancer (CRC). Results. Between 1994 and 2008, a total of 844 UC patients were followed in our clinic. A total of 275 patients entered our surveillance programme. The duration of UC was as follows: 10-15 years, n = 173 (62.9%); 15-20 years, n = 55 (20.0%); 20-25 years, n = 26 (9.5%), 25-30 years, n = 9 (3.3%); and >30 years, n = 12 (4.4%). In terms of localization, 80 patients (29.1%) had distal disease, 107 (38.9%) had left-sided disease and 88 (32.0%) had extensive colitis. Adenomatous polyp was found in six patients (2.2%). Five cases (83.3% of the polyps) were in the diseased segment and one case (16.7%) was in the non-diseased segment. Endoscopy revealed dysplasia in 11 cases (4.0%). Of the 275 UC patients, CRC was diagnosed in only three (1.1%) during follow-up. Adenomatous polyp was not found in cases with colon cancer. Conclusions. In our cases with TIC, rates of dysplasia and CRC were much lower than in other reports. The difference in rates may be explained by racial factors, specific environmental factors, intensive control of disease activity through medical therapy and effective colonoscopic surveillance programmes.