We focused on the therapeutic effect of pembrolizumab for metastatic urothelial carcinoma (mUC) and evaluated predictive factors for improving clinical outcomes. We conducted a retrospective multicenter cohort study of patients with mUC who received pembrolizumab. The endpoint was to evaluate the association between clinicopathological features and oncological outcomes. A total of 160 patients were enrolled in this study and were divided into two groups: the responder and the non-responder group, according to the best response. They were followed up for a median period of 10 months. The median overall (OS) and progression-free survival (PFS) in this study were 17 and 4 months, respectively. The responder group did not achieve median OS and it was 10 months in the non-responder group (p < 0.001). Similarly, the responder group did not achieve PFS, and it was 2 months in the non-responder group (p < 0.001). Regarding the neutrophil-to-lymphocyte ratio (NLR) after two courses of administration of pembrolizumab, patients with NLR < 3.24 had significantly better oncological outcomes than those with NLR ≥ 3.24. Multivariate analysis showed a significant association between NLR after two courses of pembrolizumab and OS. Therefore, the absolute value of NLR after two courses of pembrolizumab was a significant predictive factor for oncological outcomes.
Keywords: metastatic urothelial carcinoma; multicenter cohort study; neutrophil-to-lymphocyte ratio; oncological outcomes; pembrolizumab.