Association of baseline neutrophil-to-eosinophil ratio (NER) and neutrophil-to-lymphocyte ratio (NLR) with response to combination immunotherapy (IO) with ipilimumab plus nivolumab (ipi/nivo) in patients with metastatic renal cell carcinoma (mRCC).

Abstract

4563 Background: Previous reports have shown that the baseline neutrophil-to-lymphocyte ratio (NLR) is associated with prognosis in patients with mRCC. However, NLR has not been shown to reliably predict for response to IO. Retrospective analyses in metastatic melanoma and mRCC have shown an association of eosinophilia with improved outcomes to single agent immunotherapy. We sought to evaluate and compare the baseline NLR and NER with response to ipi/nivo in patients with mRCC. Methods: A retrospective review of patients with mRCC treated at the Vanderbilt-Ingram Cancer Center or Duke Cancer Institute with ipi/nivo was performed. Patients with clear cell histology and a baseline complete blood count with differential were included. Patients previously treated with IO were excluded. Patients were separated into groups (above and below the median) based on baseline median NER and baseline median NLR. Analyses of progression free survival (PFS) and overall survival (OS) were conducted using the log rank test. The odds ratio (OR) for objective response rate (ORR) was analyzed using Fisher’s exact test. Results: 111 patients met inclusion criteria. The median age was 60, 77% of patients were male, 68% had prior nephrectomy, 74% were naïve to systemic therapy, and 84% were IMDC intermediate/poor risk. The median NER was 25.0 and median NLR was 3.4. Patients with < median baseline NER had significant improvement in PFS, OS, and ORR (see table). Patients with < median baseline NLR had significant improvement in OS but not in PFS or ORR. Conclusions: Baseline NER was associated with improved outcomes with ipi/nivo. While both NER and NLR were associated with improved OS, only NER was additionally associated with both improved PFS and ORR. With multiple first-line treatment options for mRCC, baseline NER may serve as an early non-invasive predictor for response to ipi/nivo.[Table: see text]