Utilization and efficacy of second-line targeted therapy in metastatic renal cell carcinoma: data from a national registry

Background: It is well known that patient characteristics and survival outcomes in randomized trials may not necessarily be similar to those in real-life clinical practice. The aim of the present study was to analyse second line treatment strategies in the real-world practice and to estimate the outcomes of patients treated with second-line targeted therapy for metastatic renal cell carcinoma (mRCC). Methods: This is a retrospective, registry-based study using data from the national registry of targeted therapies for mRCC. The RENIS registry contains data on 3049 patients who started the therapy with at least one targeted agent before 31 December, 2014. Of these patients, 1029 had a record of at least two different targeted therapies and sufficient data for analysis. Survival analysis was carried out using the Kaplan-Meier method. Statistical significance of differences in survival between subgroups was assessed using the log-rank test. Results: The median overall survival from the start of second-line treatment was 17.0 months (95% confidence interval [CI] 14.5-19.5 months), 17.1 months (95% CI 14.5-19.8), and 15.4 months (95% CI 11.0-19.7) for second-line everolimus, sorafenib, and sunitinib, respectively. Patients receiving second-line everolimus were older at the start of second-line treatment, more likely to have metachronous disease, and less likely to be previously treated with cytokines or to continue to third-line treatment than patients treated with second-line sunitinib or sorafenib. Progression-free survival (PFS) correlated with PFS on first-line treatment only for everolimus. Conclusions: In this retrospective study, no significant differences in survival were observed between the cohorts treated with different second-line agents including everolimus, sorafenib, and sunitinib.