M1149 Genetic Markers and the Risk of Complicated Disease Behaviour in Crohn's Disease Patients

Abstract

Methods: IBD related CRC pts in all non-tertiary centers in The Netherlands were identified by using the nation wide network and registry of histoand cytopathology (PALGA). Pts who had IBD and CRC diagnosed synchronously or metachronously in a pathology report from January 1990 until December 2005 were included. In a 2nd search we only included pts < 65 yrs old to minimize interference with sporadic CRC. Further clinical data were obtained to assess the IBD population and to verify the diagnosis of IBD associated CRC. Of the selected pts clinical data including age, gender, type of IBD, date of diagnosis of IBD and CRC, follow-up of IBD and CRC and extend of disease were collected from patient charts. Results: The initial PALGA search identified 2734 pts suggestive for an IBD associated CRC. Of these pts 1237 were < 65 yrs old. Further analysis of the pathology excerpts within the PALGA search showed 468 pts with a possible IBD associated CRC. By December 1, 2007 we have collected data from 30 randomly selected hospitals in The Netherlands. In these hospitals 171 patient charts and pathology reports were assessed to confirm diagnosis and to collect clinical data. Overall, in 94 pts we could confirm the diagnosis of IBD related CRC (56 ulcerative colitis (59.6%), 38 Crohn's disease (41.3%)). The average IBD population per hospital was 600 pts. On average 3 pts per hospital developed a CRC in a time period of 15 yrs, consistent with a 0.5% CRC risk within 15 yrs follow-up per IBD patient and 0.03% per year per IBD patient, independent of other variables. Conclusion: The risk for IBD-associated CRC is limited in a regular, secondary IBD population. Therefore current surveillance strategies in IBD patients need to be adjusted.