Colorectal Cancer Risk in Crohn's Disease Patients After Colectomy: A Propensity-Matched Cohort Study Using a Nationwide EMR Database

Abstract Objective: To assess the risk of colorectal malignancy in CD patients with and without colectomy over time. Methods: A retrospective cohort study was conducted using the TriNetX Research Network, which includes data from 70 U.S. healthcare organizations. A total of 7,315 CD patients who underwent partial or total colectomy were matched 1:1 to 7,315 patients without surgical intervention. Patients with ulcerative colitis were excluded. CRC outcomes including colon (C18), rectosigmoid (C19), and rectal (C20) cancers were analyzed at 5-, 10-, and 20-year follow-up intervals. Hazard ratios (HR) with 95% confidence intervals (CI) were calculated, and Kaplan-Meier curves were compared using log-rank testing. Results: Among 14,630 matched CD patients, colon cancer incidence at 5 years was 5.4% in the colectomy group vs. 0.6% in the non-colectomy group (HR 8.40; 95% CI: 6.19 to 11.40). Elevated risk persisted at 10 years (5.5% vs. 0.8%; HR 7.02) and 20 years (6.1% vs. 0.9%; HR 7.06). Rectosigmoid cancer occurred in 1.5% of colectomy patients vs. 0.2% of controls (HR 7.09), and rectal cancer in 1.5% vs. 0.5% (HR 3.23). All differences were statistically and clinically significant. Conclusions: Colectomy in CD is associated with a sustained increase in CRC risk, especially in the colon and rectosigmoid junction, highlighting the need for lifelong surveillance in this population.