Baseline and early change of neutrophil to lymphocyte ratio (bNLR and ΔNLR) as prognostic factors in metastatic renal cell carcinoma (mRCC) patients treated with nivolumab: Preliminary results of the Meet-URO 15 (I-BIO-REC) study.

Abstract

752 Background: Biomarkers to select mRCC patients most likely to benefit to immune-checkpoint inhibitors are still needed. The ongoing retrospective multicentre Meet-URO 15 (I-BIO-REC) study evaluates the prognostic role of peripheral blood cells in mRCC patients treated with nivolumab. Methods:The primary endpoint of the study was median overall survival (mOS) according to bNLR. Complete blood count was collected at the first four cycles of nivolumab. NLR was defined as the ratio of neutrophil to lymphocyte (cutoff = 3) and ΔNLR the difference between NLR at 2nd cycle and bNLR (median used as cutoff = 0.3). Here we reported preliminary analyses on bNLR and DNLR. Results: From May 2016 to January 2019 189 patients started nivolumab as 2nd (62%), 3rd (25%) and > 3rd (13%) line. Median age was 69 years, 67% were male and 87% had clear cell histology. Baseline IMDC group was favorable in 26%, intermediate in 63% and poor in 11%. Lymph-nodes, visceral and bone metastases were present in 55%, 92% and 37%. mOS and progression-free survival (PFS) were 30.5 months and 9.5 months. Overall response rate (ORR) and disease control rate (DCR) were 28% and 57%. bNLR was available in 162 patients: bNLR < 3 (52%) correlated with statistically significant longer PFS [11.5 vs 5.6 months; HR 1.61 (1.09-2.39), p = 0.017] and OS [NR vs 22.4 months; HR 2.61 (1.53-4.46), p < 0.001], with similar ORR (32% vs 32%) but higher DCR (66% vs 55%) compared to NLR ≥ 3. ΔNLR was available in 136 patients: ΔNLR < 0.3 (50%) correlated with statistically significant longer PFS [17.1 vs 8.5 months; HR 1.57 (1.02-2.43) p = 0.04] and OS [medians not reached; HR 1.91 (1.04-3.51) p = 0.038], with similar ORR (39% vs 32%) but higher DCR (73% vs 56%) compared to ΔNLR ≥ 0.3. Univariate and multivariate analyses adjusted for IMDC group, line of therapy and metastatic sites, confirmed the statistically significant correlation between ΔNLR with PFS and OS and NLR with OS but not with PFS. Conclusions: Preliminary analyses of our study showed a prognostic role of bNLR and early ΔNLR in mRCC patients treated with nivolumab.