Intradural spinal metastasis to the cauda equina in renal cell carcinoma: a case report and review of the literature.

Abstract

Case description. To describe a case of intradural metastasis from a renal cell carcinoma (RCC) spread to the cauda equina, and review the pertinent medical literature. Intradural spinal metastasis is rare, accounting for 6% of all spinal metastases. Only 7 cases of intradural metastasis from a RCC to the cauda equina have been previously reported. A 41-year-old male presented with a 1-month history of severe back pain radiating to both legs. The patient underwent a right nephrectomy for treatment of a RCC 1-year before admission. Magnetic resonance imaging showed a well-demarcated, intradural extramedullary mass at the L2 vertebra. After a total laminectomy, total excision of the tumor was achieved followed by rapid improvement of the back pain. The tumor was histologically verified as metastatic RCC, identical to that of a previous tumor specimen. The patient was asymptomatic on the 1-year follow-up. Although the majority of cauda equina tumors are primary tumors, intradural metastasis should be considered before surgery in patients with previously treated RCC.