P0374 Prevalence, risk factors and clinical outcomes of malignancies in patients with Inflammatory Bowel Disease: a case-control study

Abstract Background Up to 30% of patients with inflammatory bowel disease (IBD) develop malignancies during their disease course whichconstitutes the second cause of death, after cardiovascular diseases (1,2), similar to the general population. The present study aims to investigate the prevalence, risk factors and clinical outcomes of malignancies in patients with IBD. Methods This is a retrospective study, based on prospectively recorded data from the IBD registries of two tertiary centres from 2012-2022. Patients with IBD who developed a malignancy were compared with patients with IBD without malignancies [matching 1:3 according to sex, IBD diagnosis (Ulcerative Colitis; UC, Crohn’s Disease; CD) and age (±5 years)]. Results From 2.382 IBD patients, 107 (4.5%) were diagnosed with cancer (CA) [49 (45.8%) females, 54 (50.5%) CD, median (IQR) age 61 (51.3-69.8) years and median IBD duration 10 (0-40) years at CA diagnosis] and these were matched with 321 patients with IBD who did not develop any type of CA. The majority were extra-intestinal CAs, whereas only 12 (11.2%) were diagnosed with colorectal CA. The most common extraintestinal CAs were thyroid (17, 15.5%) and prostate (17, 15.5%) followed by lung (12, 10.9%), breast (9, 8.2%) and non-melanoma skin cancer (9, 8.2%) while other types like kidney CA or cholangiocarcinoma were represented with lower rates. In the univariate analysis shorter IBD duration, inflammatory CD phenotype, ileal CD location, and treatment with other than anti-TNF biologics were protective, whereas colonic CD location and duration of treatment with immunomodulators (IMMs) were risk factors for CA development. In the multivariate analysis only inflammatory CD phenotype (OR 0.25, CI 95%0.10-0.64) and colonic CD location (OR 3.73, CI 95%1.23-11.34) remained significant (Table 1). Twelve patients (11.2%) had CA recurrence and 19 (17.8%) passed away because of the CA, with most events occurring within 50 months from CA diagnosis. In 36 patients (33.6%) IBD therapy was modified after CA diagnosis (biologics and/or IMMs ceased). However, biologics or IMM were introduced in 24.3% after a median time of 3.5 (0-18) years from CA diagnosis but their use was not associated with negative outcomes [neither on survival (p = 0.0385) nor CA recurrence (p= 0.1680)] (Figure 1). Conclusion The prevalence of malignancy in patients with IBD that are followed up in tertiary referral centers in Crete is 4.5%. CD disease phenotype (inflammatory behavior and colonic location) is associated with the development of malignancies while no association with biologics and/or immunomodulators exposure was found. Initiation of biologics or IMMs after CA diagnosis was not associated with an adverse impact neither on survival nor on CA recurrence. References 1.Jess T, Simonsen J, Jørgensen KT, Pedersen BV, Nielsen NM, Frisch M. Decreasing risk of colorectal cancer in patients with inflammatory bowel disease over 30 years. Gastroenterology. 2012 Aug;143(2):375-81.e1; quiz e13-4. 2.Lutgens MW, van Oijen MG, van der Heijden GJ, Vleggaar FP, Siersema PD, Oldenburg B. Declining risk of colorectal cancer in inflammatory bowel disease: an updated meta-analysis of population-based cohort studies. Inflamm Bowel Dis. 2013; 19: 789–99.

Topic: Inflammatory Bowel Disease
Subfield: Genetics
Field: Biochemistry, Genetics and Molecular Biology
Domain: Life Sciences