Baseline lymphocyte to monocyte ratio (LMR) and systemic inflammation index (SII) 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

751 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 baseline neutrophil to lymphocyte ratio (NLR), but here preliminary analyses on baseline LMR and SII (secondary endpoints) are reported. LMR was defined as the ratio of lymphocyte to monocyte (cutoff = 3) and SII as platelet x neutrophil/lymphocyte (cutoff = 1375). 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%. LMR was available in 150 patients: LMR ≥ 3 (44%) correlated with statistically significant longer OS [NR vs 26.8 months, HR 0.50 (0.29-0.88); p = 0.016] but not PFS (10.3 vs 9.9 months, HR 0.87 (0.58-1.31); p = 0.5) with similar ORR (34% vs 33%) and DCR (60% vs 63%) compared to LMR < 3. SII was available in 162 patients. SII < 1375 (82%) correlated with statistically significant longer PFS [11.5 vs 3.4 months; HR 2.16 (1.36-3.43), p = 0.001] and OS [NR vs 9.5 months; HR 3.87 (2.21-6.78), p < 0.001] with higher ORR (35% vs 20%) and DCR (65% vs 40%) compared to SII ≥ 1375. Univariate and multivariate analyses adjusted for IMDC group, line of therapy and metastatic sites, confirmed the statistically significant correlation between SII with PFS and OS, but not for LMR. Conclusions: Preliminary analyses of our study showed a prognostic role of baseline SII, while it is uncertain for LMR in mRCC patients treated with nivolumab.