AbstractBackgroundPredictive markers can help tailor treatment to the individual in metastatic renal cell carcinoma (mRCC). De Ritis ratio (DRR) is associated with oncologic outcomes in various solid tumors.ObjectiveTo assess the value of DRR in prognosticating survival in mRCC patients treated with tyrosine-kinase inhibitors (TKI).MethodsOverall, 220 mRCC patients treated with TKI first-line therapy were analyzed. An optimal cut-off point for DRR was determined with Youden’s J. We used multiple strata for DRR, performed descriptive, Kaplan–Meier and multivariable Cox-regression analyses to assess associations of DRR with progression-free (PFS) and overall survival (OS).ResultsPatients above the optimal cut-off point for DRR of ≥ 1.58 had fewer liver metastases (p = 0.01). There was no difference in PFS (p > 0.05) between DRR groups. DRR above the median of 1.08 (HR 1.42;p = 0.03), DRR ≥ 1.1(HR 1.44;p = 0.02), ≥ 1.8 (HR 1.56;p = 0.03), ≥ 1.9 (HR 1.59;p = 0.02) and ≥ 2.0 (HR 1.63;p = 0.047) were associated with worse OS. These associations did not remain after multivariable adjustment. In the intermediate MSKCC group, DRR was associated with inferior OS at cut-offs ≥ 1.0 (HR 1.78;p = 0.02), ≥ 1.1 (HR 1.81;p = 0.01) and above median (HR 1.88;p = 0.007) in multivariable analyses. In patients with clear-cell histology, DRR above median (HR 1.54;p = 0.029) and DRR ≥ 1.1 (HR 1.53;p = 0.029) were associated with OS in multivariable analyses.ConclusionThere was no independent association between DRR and survival of mRCC patients treated with TKI in the entire cohort. However, OS of patients with intermediate risk and clear-cell histology were affected by DRR. DRR could be used for tailored decision-making in these subgroups.