e14583 Background: Studies have suggested that concurrent corticosteroid use may decrease the efficacy of immunotherapy for cancer treatment, however, the data remains limited. The purpose of this study is to expand upon the previous literature to analyze the outcomes of patients with the following cancer sites: renal cell, lung, melanoma, urothelial, head and neck, hepatocellular, or breast cancer who received immunotherapy and steroids concurrently. Our primary objective was to analyze the overall survival (OS) and objective response rate (ORR) of patients receiving immunotherapy with corticosteroids compared to immunotherapy alone. Methods: A retrospective cohort study was conducted of patients receiving immunotherapy plus corticosteroids compared to immunotherapy alone using University of Texas Medical Branch patients. Patients receiving nivolumab, pembrolizumab, atezolizumab, ipilimumab, durvalumab, or avelumab between January 1, 2012-August 2020 with one of the following cancers were included in the analysis: Renal cell carcinoma, lung carcinoma, melanoma, urothelial carcinoma, head and neck carcinoma, hepatocellular carcinoma, and breast cancer carcinoma. The resulting sample was then separated into two arms. The experimental sample received any of the following steroids either as part of their therapeutic regimen or for symptom management and within 30 days of immunotherapy initiation or at any time during the immunotherapy regimen: dexamethasone, prednisone, methylprednisolone, or hydrocortisone. The control did not receive steroids within 30 days of initiation or during the course of their immunotherapy regimen. Weibull regression models were then constructed to compute hazard ratios for OS at 6 months, 12 months, and 3 years. ORR - complete and partial response, stable disease, and disease progression - between the two arms was assessed using a chi-squared test. Results: Two hundred and sixty patients met inclusion criteria. Of this, 164 received corticosteroids. Our sample was primarily male (70.38%), white (66.54%), and had 0-1 comorbidities (83.08%), lung cancer (45%), and metastases (81.92%). There was no significant difference between the two arms regarding sex, age, number of comorbidities, ECOG score, cancer type, or race. There was no statistically significant difference in OS between the experimental and control arm at 6 months (HR: 1.01; 95%CI 0.63-1.62), 12 months (1.02; 95% CI 0.69-1.51), or 3 years (1.06; 95% CI 0.79-1.42). There was no significant difference in ORR at 6 months between the two arms (2 = 6.3, p=0.178). Conclusions: There was no statistically significant difference in OS or PFS between the two study arms. This study suggests that corticosteroid use does not affect immunotherapy efficacy as previous literature suggests. Larger studies are needed to assess the impact of corticosteroids on immunotherapy efficacy in patients with cancer.