Prognostic value of risk stratification using blood parameters for nivolumab in Japanese patients with metastatic renal-cell carcinoma

Background Nivolumab is a standard treatment for previously treated advanced renal-cell carcinoma. However, nivolumab is effective in only a limited number of patients; therefore, we evaluated the prognostic value of several biomarkers, including inflammation-based prognostic scores and changes in these scores following nivolumab treatment in Japanese patients with metastatic renal-cell carcinoma. Methods We retrospectively reviewed the medical records of 65 patients with previously treated metastatic renal-cell carcinoma and who received nivolumab. Inflammation-based prognostic scores, including neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, lymphocyte/monocyte ratio, and Glasgow prognostic score before and 6 weeks after the treatment were recorded. Categorical variables influencing disease-specific survival were compared using Cox proportional-hazards regression models. Results Univariate analysis showed that Memorial Sloan-Kettering Cancer Center risk score (P = 0.0052), lactate dehydrogenase (P = 0.0266), lymphocyte/monocyte ratio (P = 0.0113), and platelet/lymphocyte ratio (P = 0.0017) had a significant effect on disease-specific survival. Multivariate analyses showed that platelet/lymphocyte ratio and lactate dehydrogenase were found to be independent prognostic factors for disease-specific survival (P = 0.0008, risk ratio (RR) = 7.95, 95% confidence interval, 2.16-51.64 and P = 0.0123, RR = 3.92, 95% confidence interval, 1.37-10.80, respectively). The combination of platelet/lymphocyte ratio and lactate dehydrogenase was the most significant prognostic biomarker in metastatic renal-cell carcinoma (P < 0.0001). Changes in lymphocyte/monocyte ratio and platelet/lymphocyte ratio in response to nivolumab were significant prognostic factors for disease-specific survival (P < 0.0001 and P = 0.0477, respectively). Conclusions The combination of platelet/lymphocyte ratio and lactate dehydrogenase may be a potential biomarker for estimating disease-specific survival in Japanese patients with metastatic renal-cell carcinoma treated by nivolumab.