Baseline and early change of systemic inflammation index (bSII and ΔSII) as prognostic factors in metastatic renal cell carcinoma (mRCC) patients treated with Nivolumab: Final results of the Meet-URO 15 (I-BIO-REC) study.

Abstract

5072 Background: Biomarkers to select mRCC patients most likely to benefit to immunotherapy are still needed. The retrospective multicentre Meet-URO-15 study evaluated the prognostic role of peripheral blood cells in mRCC patients treated with Nivolumab. Methods: Complete blood count was collected at the first four cycles of Nivolumab. The primary endpoint was median overall survival (mOS) according to baseline neutrophil-to-lymphocyte ratio. Secondary analyses included bSII defined as platelet x NLR (cutoff = 1375) and ΔSII defined as the difference between SII at 2ndcycle and bSII (median used as cutoff = 383). Results: From October 2015 to October 2019, 470 patients started Nivolumab as 2nd(67%), 3rd(22%) and > 3rd(11%) line. Median age was 66 years, 71% were male and 83% had clear cell histology. Baseline IMDC group was favorable in 25%, intermediate in 63% and poor in 12%. Lymph-nodes, visceral and bone metastases were present in 54%, 91% and 36%. mOS and progression-free survival (PFS) were 34.8 and 7.5 months. Overall response rate (ORR) and disease control rate (DCR) were 30% and 61%. SII was available in 404 patients: SII < 1375 (82%) correlated with statistically significant improvement of PFS [10.2 vs 4.1 months, HR 2.06 (1.54-2.76), p< 0.001], OS [46.2 vs 9.5 months, HR 3.16 (2.23-4.49), p< 0.001], ORR (35% vs 21%, p= 0.035) and DCR (67% vs 40%, p< 0.001). ΔSII was available in 360 patients: ΔSII < 383 (75%) correlated with statistically significant improvement of PFS [11.3 vs 4.7 months; HR 1.64 (1.23-2.18), p= 0.001] and OS [NR vs 21.1 months; HR 1.76 (1.21-2.56), p= 0.003], ORR (37% vs 24%, p= 0.023) and DCR (68% vs 53%, p= 0.01). Multivariate analyses adjusted for IMDC group, line of therapy and metastatic sites, confirmed the statistically significant correlation of bSII and ΔSII with OS, PFS and DCR. Conclusions: Our study showed the statistically significant correlation of lower bSII and early ΔSII with longer OS, PFS and higher DCR in mRCC patients treated with Nivolumab.