Inflammatory bowel disease (IBD) is a collective term used for two diseases: Crohn’s disease and ulcerative colitis. It is characterized by the chronic inflammation of the gastrointestinal tract. Colon cancer is one of the risks of IBD, especially in adults. The objective of this study is to analyze how the childhood onset of IBD is associated with the risk of cancer in adulthood.

This cohort study with a matched general population included a total of 14,503 IBD patients (Crohn’s: 9,405; ulcerative colitis: 4,648) aged 19 and older. A total of 92,870 controls were also included. The primary outcome of the study was the incidence of any type of cancer.

During the median follow-up of 27 years, 497 cases (3.3 per 1,000 person-years) people with IBD in childhood developed first cancers, as compared with 2,256 (1.5 per 1,000 person-years) in the controls. The mean hazard ratio of cancer in patients with IBD was 2.15 (2.6 with ulcerative colitis and 1.7 with Crohn’s disease). The highest relative risk was with gastrointestinal cancers (HR 18.0), primarily colon cancer.

The research concluded that childhood onset of IBD was associated with an increased risk of cancer, primarily colon cancer.