A matched case-control study of IBD-associated colorectal cancer: IBD portends worse outcome

Abstract

Background and objectives: The effect of inflammatory bowel disease (IBD) on outcome in patients with colorectal cancer (CRC) remains unclear. Our objective is to evaluate oncologic outcomes of patients with IBD-associated CRC.

Methods: We retrospectively reviewed a prospectively maintained database to identify patients with IBD-associated CRC. Clinicopathologic variables and overall survival were compared to patients with sporadic CRC using a 2:1 matched-controlled analysis.

Results: Fifty-five patients with IBD and CRC were identified. On univariate analysis, CRC patients with IBD had a significantly shorter median overall survival (68.2 months vs. 204.3 months, P = 0.01) compared to patients with sporadic CRC. On multivariate analysis, after adjusting for N and M stage, IBD was associated with an increased risk of death compared to sporadic CRC (HR = 2.011, 95% CI 1.24-3.23, P = 0.004). Stage 3 CRC patients with IBD in particular showed significantly decreased survival (23.0 vs. 133.9 months, P = 0.008).

Conclusions: In this study, patients with node-positive IBD-associated CRC had a significant increased risk of death and a shorter overall survival than those with sporadic disease and may require tailored adjuvant therapy and surveillance protocols. Continued investigation to elucidate the mechanisms that contribute to these observations is justified.

Keywords: colorectal cancer; inflammatory bowel disease; matched controlled study.