Molecular-targeted Therapy and Surgery May Prolong Survival of Renal Cell Carcinoma Patients with Bone Metastasis: A Multi-institutional Retrospective Study in Japan

To determine prognostic factors for overall survival (OS) in renal cell carcinoma (RCC) patients with bone metastasis in the targeted-therapy era.We conducted a retrospective multi-institutional review of the medical records of 149 RCC patients with bone metastasis. Survival was estimated using the Kaplan-Meier method and compared with the log-rank test. Univariate and multivariate Cox proportional hazard regression analyses were performed to identify independent factors associated with OS.The median OS was 13.4 months. In multivariate analysis, molecular-targeted therapy, nephrectomy and surgery for bone metastasis were independent prognostic factors. Bone-modifying agents (BMAs) were not associated with OS. The median OS of patients receiving molecular-targeted therapy after diagnosis of bone metastasis was significantly better than that of those who did not receive targeted therapy.Molecular-targeted therapy, nephrectomy and surgery for bone metastasis should be considered for RCC patients with metastasis in the bones.