Background: Skeletal metastases from renal cell carcinoma are highly destructive vascular lesions. They pose unique surgical challenges due to the risk of life-threatening hemorrhage and resistance to other treatments. The goal of this retrospective study was to evaluate factors that may affect survival after surgical treatment of metastases of renal cell carcinoma.
Methods: We performed a retrospective review of a series of 295 consecutive patients who had been treated for metastatic renal cell carcinoma at one institution between 1974 and 2004. There were 226 men and sixty-nine women. A total of 368 metastases of renal cell tumors to the extremities and pelvis were treated. The surgical procedures included curettage with cementing and/or internal fixation (214 tumors), en bloc resection (117), closed nailing (twenty-seven), amputation (four), and other measures (six). Overall survival was calculated with Kaplan-Meier analysis. The log-rank test was used to evaluate the effect of different variables on overall survival.
Results: The overall patient survival rates at one and five years were 47% and 11%, respectively. The metastatic pattern had a significant effect on the survival rate (p < 0.0001): patients with a solitary bone metastasis had the most favorable overall survival rate. Patients with multiple bone-only metastases had a better survival rate than patients with pulmonary metastases (p = 0.009). A clear-cell histological subtype was also associated with better survival (p < 0.0001). The tumor grade did not predict survival (p = 0.17). Fifteen patients (5%) died within four weeks after surgery. The causes included acute pulmonary failure (seven patients), multiorgan failure (six), cerebrovascular accident (one), and hypercalcemia (one). There were no deaths attributable to intraoperative hemorrhage.
Discussion: Survival beyond twelve months is possible for a substantial proportion of patients with metastatic renal cell carcinoma. Patients with a clear-cell histological subtype, bone-only metastases, and a solitary metastasis have superior survival rates. The presence of pulmonary metastases does not predict early death in a reliable manner, and some patients may survive for years with pulmonary and systemic disease. The data are important for surgeons to consider when choosing treatment for these patients. For example, local control of disease and implant stability are important issues for patients with a potential for a long duration of survival.
Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.