Outcome After Surgery for Colon Cancer in a National Cohort of Patients With and Without Inflammatory Bowel Disease.

Abstract

AIMS To estimate the impact of inflammatory bowel disease on survival in a national cohort of patients following surgical resection for colon cancer, and to describe the surgical treatment of colon cancer in patients with inflammatory bowel disease. METHODS Using the Colorectal Cancer Database, we included all patients ≥ 15 years of age with a diagnosis of stages I-III colon cancer treated with curative intent 2007-2021. We used Cox proportional hazards models to compare overall survival, recurrence-free survival and cancer-specific survival between patients with and without inflammatory bowel disease. Multivariable analyses were adjusted for sex, age, date of colon cancer surgery, Charlson Comorbidity Index and primary sclerosing cholangitis. RESULTS Among 35,640 patients with colon cancer, 675 (1.9%) had inflammatory bowel disease. Median age at colon cancer diagnosis was 68 years in patients with inflammatory bowel disease and 75 in those without; proportions of male sex were 55% and 49%, respectively. In patients with inflammatory bowel disease, surgical therapy was proctocolectomy in 10%, subtotal colectomy in 29% and segmental resection in 61%. From adjusted analyses, patients with inflammatory bowel disease had worse overall survival (HR = 1.38; 95% CI: 1.21-1.57), recurrence-free survival (HR = 1.33; 95% CI: 1.18-1.50) and cancer-specific survival (HR = 1.46; 95% CI: 1.23-1.73) than patients without. CONCLUSION Inflammatory bowel disease negatively influences the prognosis of colon cancer. Proctocolectomy was performed only in a minority of those with inflammatory bowel disease. Outcomes need to be improved in patients with inflammatory bowel disease developing colon cancer.