Does the Time to Start First-Line Treatment Influence the Survival of Favorable-Risk Patients With Metastatic Renal Cell Carcinoma? Results of the MetaSurv–UroCCR 79 Study

Many patients in the favorable International Metastatic renal cell carcinoma (RCC) Data Base Consortium group (F-MRC) may have a relatively indolent disease course. Surveillance and delay of systemic therapy could be an option in this specific population. However, the question whether this delay could alter patients' outcome remains unanswered. Our objective was to determine if delaying first-line treatment influences the survival of F-MRC patients.We performed a retrospective multicenter national study involving the French Network for Research on Kidney Cancer UroCCR (NCT03293563). We included treatment naive F-MRC patients. We compared the overall survival of patients with immediate medical treatment (IMT) (started less than 3 months after metastatic diagnosis) to those with delayed medical treatment (DMT).We included 90 patients treated between 2009 and 2018. The median time before occurrence of metastases from diagnosis was 28 (12-137) months. The two groups (IMT vs. DMT) were comparable for follow-up, age, sarcomatoid feature, number, and localization of metastatic sites and ECOG performance status. IMT was given in 25 (27.8 %) patients. Local treatment of metastasis (LTM) was performed in 47 (52%) patients. Patients with DMT had more LTM (63% vs. 24%, P = .001). Among patients with DMT (n = 65); 27 (41%) received a systemic treatment and median systemic treatment-free survival was 39 months (95% CI, 26.3-51.6). Median overall survival from metastasis disease diagnosis was 55 months (95% CI, 42.4-67.5) in the IMT group and 88 months (95%CI, 64-111.9) in the DMT group (P = .028). In multivariable analysis LTM was the only prognostic factor associated to survival improvement (HR: 0.33; P = .024).Selected Patients with F-MRC may safely undergo DMT. LTM positively impacted survival in this population and should be considered whenever possible. Prospective trial with a larger population is needed to confirm these results.