P679 Inflammatory Bowel Disease and cancer risk in the IBSEN study after 30 years of follow-up.

Follin-Arbelet, B.(1);Småstuen Cvancarova, M.(2);Hovde, Ø.(3);Jelsness-Jørgensen, L.P.(4);Moum, B.(2);

(1)University of Oslo, Institute of Clinical Medicine, Oslo, Norway;(2)Oslo University Hospital, Department of Gastroenterology, Oslo, Norway;(3)Innlandet Hospital Trust, Medical Department, Gjøvik, Norway;(4)Østfold University College, Østfold University College, Fredrikstad, Norway;


Inflammatory Bowel Diseases (IBD) are chronic diseases with a heterogeneous clinical course, which often cause serious complications. Previously our group has reported that male ulcerative colitis (UC) patients have an increased risk for developing colorectal cancer 20 years after diagnosis, compared to the general Norwegian population. This study aims to estimate the risk of cancer after 30 years.


Data from the Inflammatory Bowel disease in South-Eastern Norway (IBSEN) study, in which all patients diagnosed from 1990 to 1994 were included, as well as data on all cancer cases from the Norwegian Cancer Registry and mortality from the Norwegian Cause of Death Registry, were used. All IBD patients were age- and gender-matched with five controls and followed up from the date of IBD diagnosis to the date of first cancer diagnosis, death or end of follow-up (31.12.2020) whichever came first. We computed hazard ratios (HR) for all cancers combined and for cancers of digestive organs using conditional Cox regression model stratified by gender and IBD diagnosis.


In total, 756 IBD patients were included, 519 with UC and 237 with Crohn’s disease (CD). Of these, 82 UC and 35 CD patients were diagnosed with cancer during the follow-up. The most frequent cancer diagnoses were intestinal, breast and prostate cancers (Table 1). For all cancers combined, males with UC and females with CD had slightly higher risk of developing cancer compared to matched controls, however, the increased risks were not statistically significant. The same pattern was observed for cancers of digestive organs (Table 2).


Table 2.


Our data did not reveal significant differences in risk of developing cancer 30 years after diagnosis between IBD patients and age-and gender-matched controls.