MON-603 Racial Distribution of Endocrine Complications in Oncology Patients Treated with Immune Checkpoint Inhibitors

Background: Immune-related adverse events (irAEs) have been frequently described with the growing use of immune checkpoint inhibitors (ICI) in cancer treatment. While many autoimmune diseases are known to be more prevalent in certain racial groups, it is unknown if there are racial disparities in the rate of irAEs. Clinical trials reporting irAEs thus far have not explored their distribution in underrepresented minorities. It is important to study irAEs in racially diverse populations to better understand which patients are more likely to be impacted. Hypothesis: We sought to describe the demographics of a diverse cohort of patients treated with ICIs, as well as the racial distribution of irAEs. We hypothesized that there would be a significant difference among self-reported races experiencing ICI-related endocrine diseases. Methods: IRB approval was obtained to identify 411 oncology patients who were treated with ICIs between January 2011 and April 2017 from an EMR-based data repository. We collected data on age, gender, BMI, comorbidities, and median follow up time, which were further stratified according to self-identified race (White, Black, Hispanic, Asian, Other/Unknown). Endocrine adverse events were recorded according to race and were defined as events that were ≥ Grade 2 according to the Common Terminology Criteria for Adverse Events. We used the Fisher exact test for categorical variables and the Kruskal-Wallis test for continuous variables in the comparative analyses. Results: Of 411 patients treated with ICIs, 53.3% were White, 10.2% were Black, 10.5% were Hispanic, 7.5% were Asian, and 18.5% were Other/Unknown. The mean age was 65.3 years (67.8 in Whites, 63.7 in Blacks, 62.2 in Hispanics, 60.5 in Asians, 62.8 in Other/Unknown; p=0.0012). 38.4% were Female and 61.6% were Male. Mean BMI was 25.9 kg/m(2). 10.9% of all patients had pre-existing autoimmune disease (White: 11.0%, Black: 9.5%, Hispanic: 11.6%, Asian: 0, Other/Unknown: 15.8%; p=0.164). 7.3% of all patients had pre-existing thyroid disease (White: 6.9%, Black: 7.1%, Hispanic: 7.0%, Asian: 0, Other/Unknown: 11.8%; p=0.311). Mean follow up period was 8.7 months. 54 (13.1%) patients experienced any endocrine adverse effect without a statistically significant difference among racial groups (White: 16.0%, Black: 16.7%, Hispanic: 11.6%, Asian: 6.5%, Other/Unknown: 6.6%; p=0.189). 14.8% developed hypophysitis, 70.4% developed thyroid disease, 13.0% developed adrenal insufficiency, and 1.9% developed diabetes. Conclusions: Self-reported race was not associated with the development of ICI-related endocrinopathies in a diverse group of oncology patients. Further studies are needed to continue to characterize the populations experiencing immune-related endocrine complications in ICI therapy.