LAUSR

Background Prognostic outcomes and safety following treatment with pembrolizumab in patients with advanced urothelial carcinoma (UC) have not been fully elucidated in clinical practice. The aim of this study was to evaluate the oncological efficacy and safety of pembrolizumab after failure of platinum-based chemotherapy in Japanese patients with advanced UC in a routine clinical setting. Methods This retrospective study included 41 consecutive Japanese patients with advanced UC treated with pembrolizumab as second-line or greater therapy at Iwate Medical University Hospital from January 2018 to April 2019. Results The mean follow-up period was 6.2 months. The objective response rate, median progression-free survival, and median overall survival were 15%, 2.5 months, and 11.9 months, respectively. Univariate analysis identified poor performance status (> 1), liver metastasis, two or more metastatic organs, low hemoglobin levels, two or more prior regimens, high baseline C-reactive protein levels, higher relative C-reactive protein level change after 6 weeks, and higher relative neutrophil-to-lymphocyte ratio change after 6 weeks as significant predictors of overall survival. Among these factors, poor performance status (> 1), two or more metastatic organs, and higher relative neutrophil-to-lymphocyte ratio change after 6 weeks were identified as independent predictors of overall survival in multivariate analysis. Conclusions The introduction of pembrolizumab can result in favorable cancer control outcomes in Japanese patients with advanced UC, and the prognosis of these patients can be stratified according to three potential parameters, including poor performance status, high number of metastatic organs, and higher relative neutrophil-to-lymphocyte ratio change.