Adjuvant immunotherapy for patients with renal cell carcinoma at increased risk of recurrence following resection: A National Cancer Database analysis.

649 Background: Radical nephrectomy is the standard management for locoregional renal cell carcinoma (RCC); however, patients with adverse pathological features are at increased risk of recurrence. IMmotion010 and KeyNote 564 trials investigated the adjuvant role of immune checkpoint inhibitors (ICI) for high-risk clear cell RCC (ccRCC) and have yielded conflicting results. We aimed to investigate real-world survival outcomes associated with the adjuvant use of ICI in high-risk ccRCC using the National Cancer Database Methods: In this nationwide contemporary cohort study, patients with newly diagnosed non-metastatic high-risk clear cell RCC undergoing radical nephrectomy between 2015-2019 were included. High-risk RCC was defined as cT2 with Fuhrman grade 4 or cT3a with Fuhrman grade 3/4 or cT3b/T3c/T4 with any grade, or TxN+ any grade. Patients receiving adjuvant ICI were classified as Group A and patients who did not receive adjuvant ICI were classified as Group B. Inverse probability weighting (IPW)-adjusted Kaplan Meier curves were utilized to compare overall survival (OS) between the groups and cox proportional hazard models were utilized to identify the predictors for OS. Results: Overall, 768 patients met the inclusion criteria; 270 patients in Group A and 498 patients in Group B. The mean age was 60.5(10.6) years, and 70.8% of patients were males (Table). The use of ICI in the adjuvant setting for high-risk RCC increased from 17.4% in 2015 to 61.8% in 2019. The unadjusted and IPW-adjusted Kaplan Meier 5-year overall survival was similar in the two groups [Unadjusted: 36.8% in Group A vs 50.1% in Group B, p=0.30 and adjusted: 39.5% in Group A vs 47.9% in Group B, p=0.17]. The use of adjuvant ICI did not appear to be an independent predictor for OS on multivariable cox regression analysis (HR=1.14, p=0.31) Conclusions: Adjuvant ICI therapy in non-metastatic high-risk ccRCC might not be associated with a benefit in overall survival. [Table: see text]