S105 Association of Inflammatory Bowel Disease With Melanoma and Non-melanoma Skin Cancers- A Nationwide Study

Abstract

Background: Studies have shown that patients with inflammatory bowel disease (IBD) are at risk for several malignancies. However, the national burden of melanoma (MSC) and non-melanoma skin cancer (NMSC) amongst the IBD population is not widely available. In this study, our aim is to determine the prevalence and association of melanoma and non-melanoma skin cancer (NMSC) in patients with IBD in the United States population. Methods: A retrospective cross-sectional study on Nationwide Inpatient Sample (NIS 2016-2018) was performed in adult US hospitalizations. We identified IBD (Crohn’s Disease-CD and Ulcerative Colitis-UC) using ICD-10 codes. Prevalence MSC and NMSC (squamous cell carcinoma, basal cell carcinoma, and Merkel cell carcinoma) were identified. We performed univariate (unpaired t-test and chi-square) and mixed-effect multivariate regression analyses to identify the prevalence and association of IBD with skin cancers. Results: Out of 87,761,798 USA hospitalizations, 583,765 (0.67%) had CD and 346,515 (0.39%) had UC. Overall prevalence of MSC was 62435 (0.07%), NMSC [squamous cell carcinoma, basal cell carcinoma, and Merkel cell carcinoma] was 4760 (0.01%), 9500 (0.01%) and 4765 (0.01%), respectively. Prevalence of MSC was higher amongst UC (0.13% vs CD: 0.07% vs non-IBD: 0.07%) in comparison without IBD. The prevalence of NMSC was similar (0.01%) in IBD and non-IBD groups. (P < 0.0001) In multivariable regression analysis, we found UC was associated with 51% higher odds (aOR: 1.51, 95%CI 1.22-1.85, P = 0.0001) of having MSC in comparison without IBD. There was no significant association between MSC & CD (0.87, 0.69-1.09, P = 0.2215) and NMSC & IBD (UC: 1.04, 0.58-1.89, P = 0.8867; CD: 1.25, 0.67-2.34, P = 0.4763). Conclusion(s): Our study found an association between melanoma skin cancer with ulcerative colitis. More prospective studies are needed to evaluate this relationship and determine predictors associated with melanoma and non-melanoma skin cancer. Early identification of risk factors will help mitigate the burden of IBD-related skin cancers. The limitation of our study was missing clinical data on the severity of IBD, the establishment of causality between IBD and skin cancer, and the relationship with medication use.