e17095 Background: sRCC have a generally poor prognosis though recent clinical trial data suggest improved outcomes with CPI. We present a real-world experience of metastatic sRCC patients (pts) treated with a variety of CPI. Methods: Pts with sRCC treated with CPI Cleveland Clinic from 1/1/2015 to 12/31/2019 were identified. Overall survival (OS) was estimated using Kaplan-Meier and compared by log rank test. Results: Of 28 eligible pts identified with sRCC, median age 58, 82% Caucasian, all KPS score > 80%, 86% had IMDC intermediate/poor risk disease, 75% were clear cell, and 71% had prior nephrectomy. 46.4% had prior non-CPI systemic therapy. CPI therapy in this cohort included: 46% nivolumab monotherapy, 18% axitinib/pembrolizumab, 21% ipilimumab/nivolumab, 4% atezolizumab/bevacizumab, 7% atezolizumab, 4% carboplatin/pemetrexed/pembrolizumab. At a median follow up of 13.6 months (range 6.5-31.4), ORR was 36% (4% CR, 32% PR) and median OS was 13.8 months (95% CI: 9.23-NA). Median time to response was 3.2 months (range 2.4-13.1) and median duration of response was 8.1 months (range 0-25.5). Ten of the 13 patients started subsequent therapy due to progression. At the time of analysis, 39% were still alive and 25% of patients were still on initial I/O therapy (7+ -30+ months). There were no clear correlations between specific disease-related factors (including IMDC risk, time-to treatment of > or < 1 year, or prior systemic therapy) and response (all were p > 0.05). Conclusions: ORR and CR rates were lower in this real-world population of metastatic sRCC pts compared to clinical trial data, which should be a result of various CPI treatments and lines of treatment. However, these data highlight the heterogeneity of sRCC in general and need for additional investigations into impact of percentage of sarcomatoid features, genomic analyses, line of therapy, and CPI choice to optimize outcomes in sRCC pts.