P237 Prevalence of dysplasia and colorectal cancer in Ulcerative Colitis patients from a referral center in Latin America

Junior, R.S.F.(1);Carvalho, M.F.(1);Silva, J.C.(1);Barros, L.L.(1);Azevedo, M.F.C.(1);Carlos, A.D.S.(1);Oba, J.(1);Hashimoto, C.L.(1);Cançado, E.L.R.(1);Damiao, A.O.M.C.(1);Sipahi, A.M.(1);

(1)University of São Paulo School of Medicine, Gastroenterology, São Paulo, Brazil

Background

Ulcerative colitis (UC) is a chronic inflammatory disease characterized by relapsing and remitting course of bloody diarrhea. UC patients are at higher risk of dysplasia and colorectal cancer (CRC) when compared to the general population, especially those with primary sclerosing cholangitis (PSC), long-standing disease and active inflammation. The aim of this study was to determine the prevalence of dysplasia and CRC in a large cohort of UC patients in Latin America.

Methods

This study was a retrospective analysis of all UC patients registered and followed-up in our outpatient clinic between January 2010 and September 2020. The diagnosis was confirmed by clinical, endoscopic, histopathological, and radiologic findings according to current guidelines. CRC was confirmed by one or more experienced pathologists. Medical records were abstracted for the data: demographic characteristics; duration, extent, and treatment of UC; dysplasia and cancer.

Results

In total, 560 patients with UC were identified. Of all cases, 364 (64.8%) had pancolitis, 115 (20.5%) had left side colitis and 81 (14.4%) were diagnosed with proctitis. There was a slight predominance of female, 331 (59.1%). The mean age at inclusion was 48 years. Among these patients 11.2% had concomitant PSC. Aminosalicylates were the most common treatment in 70% of our cohort, whereas 40% were treated with immunobiologics at any time during UC course. The length of the disease was between 10 to 20 years in 42% of cases and from 20 to 30 years in 17% of them. In our analysis the prevalence of dysplasia was 21%. Five of them were of high grade, which occurred in whom the length of the disease was between 10 to 20 years. In the majority of cases dysplasia was related to the inflammatory burden of UC (75.2%) and 37 patients were diagnosed with sporadic dysplasia. Seven cases (1.25%) of colorectal cancer were found (median time from UC diagnosis to CRC = 18 years), which two of these patients had concomitant PSC. All UC‑CRC patients had extensive colitis.

Conclusion

Recent studies have suggested that the risk of CRC in UC population has decreased during the last decades due to tight control treatment and adequate endoscopic surveillance. In Latin America data on the prevalence and prognosis of UC‑CRC patients are scarce. Herein we report the frequency of UC-related dysplasia and UC-CRC in Brazil over a period of 10 years. Our results revealed higher prevalence rates when compared to underdeveloped countries, such as India and China. Longer disease duration and extensive colitis were identified as important risk factors for developing CRC in accordance with the literature. Further research is warranted to better identify ethnical and environmental risk factors in this population.