P682 Elderly onset inflammatory bowel disease is a risk factor for gastric cancer development
L.H. Nissen*1, E.L. Assendorp1, C.S. van der Post2, L.A.A.P. Derikx1, D.J. de Jong1, W. Kievit1, M. Pierik3, T. van den Heuvel3, R. Verhoeven4, L. Overbeek5, F. Hoentjen1, I.D. Nagtegaal2
1Radboud University Medical Center, Department of Gastroenterology and Hepatology, Nijmegen, Netherlands, 2Radboud University Medical Center, Department of Histopathology, Nijmegen, Netherlands, 3Maastricht University Medical Center, Department of Gastroenterology and Hepatology, Maastricht, Netherlands, 4Dutch Cancer Registry, Epidemiology, Eindhoven, Netherlands, 5PALGA, the Nationwide Network and Registry of Histo- and Cytopathology, Biomedical Research, Utrecht, Netherlands
In inflammatory bowel diseases (IBD), both chronic inflammation and medication-induced immunosuppression increase the risk of (extra-)intestinal malignancy development. An increased risk for gastric cancer (GC) was previously suggested, particularly for patients with Crohn's disease (CD).
At present it is unclear whether chronic inflammation and/or impaired immunosurveillance play a role in the GC development in IBD. Furthermore, it is unknown whether the clinical course of GC in IBD is different from the general population.
The aim of this study is to compare the clinical course of GC in IBD with the general GC population and to explore potential risk factors for the development of GC in IBD patients.
From the Dutch Pathology Registry we identified all patients with IBD and GC in The Netherlands between January 2004 and December 2008. Only adenocarcinomas were included. To identify risk factors for GC in IBD, we performed a nested case-control study with controls from the IBD South Limburg Cohort (IBDSL), a population-based IBD cohort. Data about GC incidence and outcomes in the general population were obtained from the regional Eindhoven Cancer Registry (ECR).
For relative risk (RR) determination two strategies were applied to estimate the Dutch IBD population: first a national report of the Dutch National Institute for Public Health and Environment based on general practitioner registrations and secondly epidemiological data from the European Crohn's and Colitis Organisation.
For statistical analyses a Chi-square test for categorical data was used. Variables with a p value of <.1 in univariate analyses were included in a multivariate logistic regression analysis with backward elimination to determine risk factors.
We identified 59 patients with confirmed diagnoses of IBD and GC. We found that IBD patients with GC were significantly older at IBD diagnosis than IBD controls (mean age 57.9 year versus 43.1; p < 0.01). Ulcerative colitis (UC) was more frequent in the GC group versus IBD controls (69.5 % versus 51.4 %; p < 0.01).
In the ECR, 1339 non-IBD patients with GC were identified. No differences in age at diagnosis, gender, tumor location, tumor differentiation and survival were observed between the IBD patients and the general population.
The Dutch IBD population was estimated between 57,100 and 83,148 patients, resulting in a RR for gastric cancer development for IBD of 1.3-1.8 (UC 1.5-2.5; CD 0.6-1.2).
Elderly onset IBD seems a risk factor for development of GC in IBD patients. The clinical course of GC was not different between patients with and without IBD. The increased RR to develop GC in IBD can be mainly attributed to the increased RR in UC patients.