Population-based studies of site-specific cancer risk in patients with inflammatory bowel disease (IBD) according to IBD phenotype and treatment are lacking.
Dr Tine Jess and colleagues from Denmark studied cancer risk in a well-characterized population-based IBD cohort from North Jutland County, Denmark.
A total of 1,515 patients were diagnosed with ulcerative colitis (UC) and 810 with Crohn’s disease (CD) during 1978–2002.
Patients were followed until 2010 for occurrence of incident cancer, identified in the Danish Cancer Registry.
|Patients with CD had a 55% increased risk of cancer overall|
|American Journal of Gastroenterology|
The research team compared observed numbers of cancer with expected numbers, and presented as standardized incidence ratios (SIRs) with 95% confidence intervals (CIs).
Patients with ulcerative colitis were not at increased risk of cancer overall despite increased risk of prostate cancer.
The researchers found that patients with CD had a 55% increased risk of cancer overall related to young age, colonic disease, smoking, and thiopurine exposure.
Patients were at increased risk of small bowel cancer, lung cancer, colorectal cancer in males, cervical dysplasia, and non-Hodgkin lymphoma.
Dr Jess' team concludes, "Patients with CD, but not UC, have an overall excess risk of cancer."
"Clinical characteristics of IBD patients at excess risk differ by cancer subtype."