Massive endoprosthetic replacement for bone metastases resulting from renal cell carcinoma: factors influencing patient survival.

BACKGROUND:
Surgery remains the main treatment of bone metastases due to renal cell carcinoma (RCC). We reviewed 135 patients treated with resection and endoprosthetic replacement (EPR) and examined clinico-pathological factors predicting survival.

METHODS:
Surgical and oncological outcomes were examined using a prospectively maintained database between 1976 and 2012. Survival rates were calculated by Kaplan-Meier method. Multivariate analyses were performed to investigate factors predictive of increased survival.

RESULTS:
At diagnosis, 81 patients had synchronous RCC and bone metastases and the remaining developed metachronous metastases after primary treatment for RCC. The majority were solitary tumours (75%) and 77% had ≥ one concurrent visceral metastases. The median age at surgery was 61 years old (IQR 53-69). The median follow-up was 20 months (IQR 10-43) and the overall survival was 72% at one-year. This declined to 45% and 28% at three and five-years, respectively. After adjustments for prognostic factors, there was an increased risk of death in patients with multiple skeletal metastases (HR = 2), ≥one visceral metastases (HR = 3) and local recurrence (HR = 3) (all p ≤ 0.01). Ten patients required revision (7%) and the risk of revision was 4% at one-year and remained low at 8% from two years postoperatively.

CONCLUSION:
Patients with solitary bone lesions and no visceral metastases should be considered for bone resection and EPR. As survival beyond one-year can be expected in a majority of patients and the risk of further surgery after EPR is low, patients with multiple skeletal metastases and visceral metastases should also be considered.