Survival in Patients With Primary Metastatic Renal Cell Carcinoma Treated With Sunitinib With or Without Previous Cytoreductive Nephrectomy: Results From a Population-based Registry

ObjectiveTo evaluate the effect of cytoreductive nephrectomy (CN) on overall survival (OS) in primary metastatic renal cell carcinoma (mRCC) patients treated with first-line sunitinib.Patients and MethodsPatients with primary mRCC treated with first-line sunitinib were selected from a Dutch population-based registry. A propensity score was calculated reflecting the probability of a patient undergoing CN prior to sunitinib using a set of known covariates, such as the Memorial Sloan Kettering Cancer Center and International mRCC Database Consortium risk factors. After propensity score matching, differences in OS were analyzed using the Kaplan-Meier method and a multivariable Cox proportional hazards model was used to evaluate the effect of CN on OS.ResultsA total of 227 patients met the selection criteria; 74 patients (33%) underwent CN prior to sunitinib. In the matched population, the median OS of patients who underwent CN was 17.9 months compared to 8.8 months for patients treated with sunitinib only. Multivariable analysis showed that CN was an independent predictor of OS (hazard ratio 0.61, 95% confidence interval: 0.41-0.92). A subgroup analysis of patients with a time to targeted therapy of <1 year showed a median OS of 12.7 months for patients treated with CN compared to 8.0 months for patients treated with sunitinib only. The corresponding hazard ratio was 0.67 (95% confidence interval: 0.46-0.98).ConclusionThis study suggests that CN may be effective. However, the benefit was modest when correcting for time from diagnosis to sunitinib. One important limitation is the use of a registry (with retrospectively collected data), which made it impossible to correct for unmeasured characteristics that could be associated with treatment choices or survival.