February 25, 2020
What is the risk of extracolonic cancers following total colectomy in IBD?
Patients with IBD have an increased risk of malignancy that persists after colectomy. Healthcare providers should remain vigilant.
Mark-Chistensen A, Erichsen R, Veres K, et al. Extracolonic cancer risk after total colectomy for inflammatory bowel disease: A population-based cohort study. J Crohn’s Colitis. Epub ahead of print December 11, 2019; https://doi.org/10.1093/ecco-jcc/jjz199
To document the risk of extracolonic cancers after total colectomy in IBD patients, researchers analyzed data from two national Danish registries. Data were available for 3,441 ulcerative colitis (UC) patients and 989 Crohn’s disease (CD) patients who had undergone colectomy between 1977 and 2013, with 54,183 person-years of follow-up post-colectomy. Patients underwent the surgery a mean 3.5 years after initial IBD diagnosis and were a mean 36.6 years of age at the time of colectomy.
Results showed that 372 patients were diagnosed with extracolonic cancer during follow-up, which was 1.1 times the expected incidence in the general Danish population (Standardized incidence ratio [SIR] = 1.1; 95% Confidence Interval [CI], 1.0–1.2). The risk of overall extracolonic cancer was increased among patients with CD who had a total colectomy (SIR = 1.5; 95% CI, 1.2–1.8) but not those with UC (SIR = 1.0; 95% CI, 0.9–1.2). However, the risk of hepatobiliary cancer was raised for UC patients (SIR = 2.0; 95% CI, 1.4–2.7). After excluding the first three years post-colectomy, the authors found patients with CD and total colectomy still had an increased risk of intestinal extracolonic cancers (SIR = 3.1; 95% CI: 1.6–5.5), head and neck cancers (SIR = 5.3; 95% CI, 1.7–12.3) and immune-mediated cancers (SIR = 1.5; 95% CI: 1.0–2.2).
The authors concluded that higher risk of overall and specific extracolonic cancers among CD patients compared to UC patients “presumably reflects differences in the clinical course and treatment” of the two diseases after total colectomy.
Study Design: Retrospective cohort
Allocation: Not applicable
Setting: Population-based national registries
Level of Evidence: 2b (Oxford Levels of Evidence)