Detection Rate of Colorectal Dysplasia in Inflammatory Bowel Diseases

Background:
The improvement in the quality of endoscopic equipment that aids in the diagnosis in cases of suspected dysplasia, associated with the expertise of endoscopists in inflammatory bowel diseases (IBD), has notably increased the detection of colorectal dysplasia in this population. Early identification of dysplasia is an essential pillar in the prevention of colorectal cancer in patients with IBD. Aim: To evaluate the detection rate of colorectal dysplasia through colonoscopy in patients with IBD in a Brazilian referral center.
Methods:
Data were retrospectively collected from patients undergoing surveillance colonoscopy, diagnosed with IBD, who were being monitored at a referral hospital in Brazil between January 2021 and May 2024. All colonoscopies that performed anatomopathological examination through the collection of biopsies were analyzed and described through the analytical study.
Results:
A total of 1,405 colonoscopies were performed in patients with IBD during the study period. Targeted biopsies of suspicious lesions, with or without the aid of chromoscopy, were performed in 736/1,405 (52.4%). Of the 736 patients for whom biopsies were collected, 359/736 (48.8%) had ulcerative colitis (UC) and 377/736 (51.2%) had Crohn’s disease (CD). Dysplasia rates were detected in 92/1,405 (6.5%). Low-grade dysplasia accounted for 85/92 (92.4%), followed by high-grade dysplasia (3/92 (3.3%) and neoplasia (4/92 (4.3%). The mean age of patients with dysplasia was 57.8 years, of which 75% were over 50 years. In the distribution by sex, the highest detection of dysplasia was in females in those with UC (65.5%), while in CD, males were the most prevalent (62.2%). The highest percentage of dysplasia was detected in those with UC 50/92 (54.3%), with low-grade dysplasia in 92%, high-grade dysplasia in 2% and neoplasia in 4%. The neoplasias of the cases presented were located in the rectum. While in CD, low-grade dysplasia was present in 90.5%, high-grade dysplasia in 4.8% and neoplasias located in the right colon and anal canal in 5%. The right colon was the segment most affected by dysplasia, both in UC and CD (48.9%). Of the dysplasias found in the rectum, two-thirds (66.7%) were in patients with UC and one-third (33.3%) in CD. At the time of examination, 67.4% of patients diagnosed with dysplasia were in endoscopic remission of IBD.
Conclusions:
Endoscopic surveillance of patients with IBD is essential for detecting dysplasia and colorectal cancer, with a major impact on prognosis. A thorough endoscopic examination with biopsies of suspicious areas is desirable. The authors highlight that the presence of endoscopic activity should not be a limiting factor for dysplasia screening and conclude that, although infrequent, rectal dysplasia can also be observed in CD.