SEVERITY OF LIVER DISEASE PREDICTS COLORECTAL DYSPLASIA IN IBD PATIENTS WITH PSC

Abstract INTRODUCTION Inflammatory bowel disease (IBD) increases the risk of colorectal cancer (CRC). Co-existence of IBD and primary sclerosing cholangitis (PSC) is known to increase the CRC risk. Annual colonoscopies are often recommended for early detection. However, the specific clinical risk factors in IBD-PSC patients remain incompletely characterized. This study aimed to identify clinical indicators associated with dysplasia or CRC among patients with IBD and PSC. METHODS We performed a retrospective review of electronic medical records for patients aged ≥ 18 years, diagnosed with both IBD and PSC, between January 2010 and March 2025. Inclusion criteria required a diagnosis of IBD and PSC (ascertained via ICD codes). Exclusion criteria included prior colonic surgery (e.g., colectomy). We divided patients into two groups: cases—those with IBD-PSC who had a prior diagnosis of CRC or dysplasia; controls—those with IBD-PSC without CRC or dysplasia. Clinical and demographic variables were compared between groups. T-tests (or appropriate equivalent) were used to assess significance, with p < 0.05 considered statistically significant. RESULTS A total of 168 patients met inclusion criteria: 37 (22%) cases and 131 (78%) controls. The cohort was majority male (n = 106, 63%) and white (n = 87, 52%). Ulcerative colitis was the most common IBD subtype (n = 128, 76.1%). Dysplasia was found in 27 cases (72.9%), most of which was low-grade, and 10 (27.0%) had CRC. The right colon was the most common location for dysplasia or CRC (n = 17, 45.9%). Symptomatic PSC was more frequent in cases (81%) than controls (45%), while PSC-specific therapeutic intervention (62.1% vs. 38.1%). Liver cirrhosis was more prevalent among cases than controls (70.2% vs. 40.4%). Ulcerative colitis subtype (p = 0.003), receipt of PSC therapies (p = 0.009), and presence of cirrhosis (p = 0.001) were significantly associated with Dysplasia or CRC. CONCLUSION Our findings indicate that advanced or uncontrolled liver disease—evidenced by symptomatic PSC requiring intervention, presence of cirrhosis—and ulcerative colitis are significant clinical risk factors for colorectal dysplasia or CRC in patients with PSC-IBD. These observations are consistent with prior studies showing reduced risk of CRC/dysplasia risk after liver transplantation, possibly due to improvements in liver function or bile acid metabolism. One hypothesis is that in advanced PSC, altered bile acid profiles contribute to carcinogenesis in the colon, perhaps compounded by underlying inflammation. Prospective studies are vital to refine risk stratification in this vulnerable population and to guide optimized surveillance protocols.