Stricturing Phenotype Predisposes to Small Bowel and Colorectal Malignancy in Crohn's Disease

Carcinogenesis is a major complication in patients with inflammatory bowel disease (IBD). We report the data of Crohn's disease (CD)-associated intestinal malignancy in our IBD cohort.

Retrospective analysis of data from prospectively maintained medical records of 1416 CD patients diagnosed or under follow up from January 1st 2013 to December 31st 2023.

A total of 1416 patients were included (13037.9 person-years of follow-up with mean age at diagnosis 27.62 ± 11.8 years, 64.1% males, disease duration: 9.2 ± 6.7 years). Eighteen patients (1.27%) developed intestinal malignancy at a mean age of 46.7 ± 14.2 years after 15.9 ± 10.3 years of disease. Colorectal carcinoma (10/1416) was most frequent, followed by jejunal (4/1416), anal canal (3/1416), and ileal (1/1416) cancers. All luminal malignancies occurred in stricturing disease, while anal canal carcinoma occurred in chronic perianal fistulizing disease with anal stricture. The cumulative risk of malignancy in stricturing disease was 1.5%, 8.3%, and 25.1% in the first, second, and third decades of disease, respectively. Independent risk factors included older age at CD diagnosis, longer disease duration, stricturing phenotype, and active smoking. The standardized incidence ratio (SIR) for intestinal malignancy was 95.36 (95% CI: 52.98-143.04), nearly 95-fold higher than the general population.

The incidence rate of intestinal malignancy was 1.27% in our CD cohort with standardized incidence rate of 95.3. Stricturing disease predisposed to small bowel and colorectal carcinoma. Carcinoma in anal canal was seen in chronic perianal fistulizing disease with anal canal stricture.