The Association of Clinical Outcomes with Posttreatment Changes in the Relative Eosinophil Counts and Neutrophil-to-Eosinophil Ratio in Patients with Advanced Urothelial Carcinoma Treated with Pembrolizumab

Abstract

Background: To evaluate the association of clinical outcomes with posttreatment changes in the relative eosinophil count (REC) and neutrophil-to-eosinophil ratio (NER) in patients with advanced urothelial cancer (UC) treated with pembrolizumab. Materials and Methods: We retrospectively analyzed 105 patients with advanced UC who received pembrolizumab after the failure of platinum-based chemotherapy. The REC and NER before and three weeks after pembrolizumab were recorded. A receiver operating characteristic curve was used to determine the optimal cut-off values for analyzing the risk. Results: There were no significant differences in the overall survival (OS) between the REC ≥ 4.8% and < 4.8% groups and the NER ≥ 13.7 and < 13.7 groups before pembrolizumab (p=0.997 and 0.669, respectively). However, a significant difference in the OS was confirmed between the increased and decreased REC groups and between the decreased and increased NER groups at 3 weeks after pembrolizumab (p< 0.001 and 0.002, respectively). Multivariate analyses revealed that an Eastern Cooperative Oncology Group Performance Status ≥ 2 (P=0.003), albumin < 3.7 g/dl (p=0.002), LDH > 246 U/L (p=0.011), disease site ≥ 3 organs (p=0.019), decreased posttreatment REC (3 weeks later) (p=0.002) and increased posttreatment NER (3 weeks later) (p=0.022) were independent prognostic factors for a worse OS. Conclusion: An increased REC and decreased NER after pembrolizumab may be significant early predictive markers of improved clinical outcomes in patients with advanced UC receiving pembrolizumab. Keywords: urothelial carcinoma, pembrolizumab, eosinophil, neutrophil-to-eosinophil ratio