Clinical Characteristics and Prognosis of Renal Cell Carcinoma With Spinal Bone Metastases

Background The prognosis of renal cell carcinoma (RCC) with spinal bone metastasis (sBM) varies greatly. In this study, we aimed to define the clinical characteristics and prognostic factors of RCC with spinal bone metastasis (sBM) in our center. Methods The clinical and medical records of RCC patients with sBMs were collected. The gender, age, time of BM, the extent of BM, the number of BMs, the presence or absence of visceral metastasis, and the pathological type of BM were investigated. All patients were followed up regularly. Overall survival (OS) was calculated from the date of BMs diagnosis to death or last follow-up using Kaplan-Meier method and modelled with Cox regression analysis. Results Forty-three RCC patients with sBM were collected. sBM was found synchronously in 30 patients (70%) and metachronously in 13 patients (30%). The median survival time was 30 months in 13 patients (30%) with solitary sBM and 19 months in 30 patients (70%) with multiple sBMs (P = 0.002). Visceral metastasis occurred in 12 patients (28%) with the median survival time of 17 months, while the other 31 patients (72%) had no visceral metastasis with the median survival time of 29 months (P<0.001). En-block resection was done in 10 patients with median survival time of 40.1 months. Non-en-block resection were done in 33 patients with median survival time of 19.7 months (P<0.001). Multivariate COX regression analysis showed that MSKCC score, number of BM, visceral metastasis, and en-block resection are the independent prognosis factors of RCC patients with sBM. Conclusions MSKCC risk stratification, number of sBM, visceral metastasis and en-block resection are significant prognostic factors for OS in RCC patients with spinal BM. Therefore, for selected patients who has solitary spinal BM with no visceral metastasis, en-block resection of spinal BM can potentially prolong survival and is the treatment of choice.