TIM3 expression on tumor cells predicts response to anti-PD-1 therapy for renal cancer.

This study aimed to identify novel prognostic biomarker for advanced renal cell carcinoma (RCC) patients treated with anti-PD-1 therapy, using quantitative multi-immunofluorescence (IF) analysis of tumor immunity. Twenty-five consecutive patients who had metastatic or unresectable RCC treated with anti-PD-1 therapy were studied. The patients were divided into a responder group (n = 12) and a non-responder group (n = 13). Quantitative multi-IF staining was performed on biopsy or surgical kidney samples using a panel of antibodies. Sections were scanned using a Mantra microscope, and the images were analyzed with inForm™ software. Responders had significantly higher rate of TIM3-positive tumor (100% versus 53.9%, p < 0.01) than non-responders. Multi-IF analysis showed that TIM3 expression on tumor cells was most strongly related to response to anti-PD-1 therapy, while some of the known immune-related prognostic factors in RCC (CD45RO, FOXP3, VEGF, PD-L1, PD-L2, CD163) had no significant association. Patients with TIM3-positive tumor showed significantly longer overall survival (not reached median time versus 6.0 months, p < 0.01) and progression-free survival (18.9 versus 1.1 months, p < 0.01) than those with TIM3-negative tumor. Immunohistochemistry study using samples obtained after anti-PD-1 therapy showed infiltration of CD163 macrophages and release of HMGB1, a ligand of TIM3, in necrotic tumor area. In conclusion, our study found clinical correlation between TIM3 expression on tumor cells and response to anti-PD-1 therapy. Further studies are warranted to verify whether TIM3 expression on tumor cells before systemic therapy predicts the efficacy of anti-PD-1 therapy for RCC in the clinical setting.

Prognostic outcomes and safety in patients treated with pembrolizumab for advanced urothelial carcinoma: experience in real-world clinical practice.

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.