P069 MALIGNANCY RISK IN VETERAN PATIENTS WITH INFLAMMATORY BOWEL DISEASE: A RETROSPECTIVE COHORT STUDY

Abstract

The association between inflammatory bowel disease (IBD) and colorectal cancer is well-known. However, the relationship between IBD and other malignancies has been less clearly defined in the literature to date. The objective of this study was to evaluate the types of malignancies that veteran patients with IBD at our facility have been diagnosed with. Additionally, we were interested in seeing whether there was a temporal relationship between the time of IBD diagnosis and the time to cancer diagnosis. We performed a retrospective cohort study using patient medical records at the Michael E. DeBakey VA Medical Center in Houston, TX. The cohort consisted of 676 patients with a confirmed diagnosis of IBD. Of these patients, 120 had been diagnosed with a malignancy between 1990 and 2018. The medical records were reviewed and data concerning patient gender, race, ethnicity, age at IBD diagnosis, type of cancer diagnosis, and age at cancer diagnosis were analyzed. Out of the 676 patients at our facility with a known diagnosis of IBD, 99.3% were male, 0.7% female, 96.1% Caucasian, 3% black, and 0.9% of other races/ethnicities. The average age at IBD diagnosis was 50.6 years. In the study period, 120 IBD patients were diagnosed with a malignancy. The most commonly represented malignancies were prostate (25.8%), non-melanoma skin cancers (15%), lung (12.5%), colorectal (12.5%), and bladder (10%). The mean time from IBD diagnosis to cancer diagnosis was 19 years (6.9). In a cohort of Veterans with IBD who were subsequently diagnosed with cancer, prostate cancer was the most common, followed by lung, colorectal and bladder cancer. Most cancers occur greater than 10 years after IBD diagnosis. The prevalence of observed cancers after IBD diagnosis is higher than the expected age-adjusted cancer prevalence in the non-IBD population.