Renal cell carcinoma: a rare source of cauda equina metastasis. Case report.

The authors present the case of a patient in whom intradural metastasis from renal cell carcinoma spread to the cauda equina. To the authors' knowledge, this is only the second report of its kind. This male patient had undergone nephrectomy for the treatment of renal cell carcinoma for 5 years and was diagnosed as having metastatic lung disease 1 year prior to admission. The patient presented with lower back pain that radiated to both legs, but he exhibited no sensorimotor deficits. The majority of cauda equina tumors are primary tumors, and metastases are very rare. The literature is reviewed with reference to current molecular genetic paradigms of metastatic renal cell carcinoma.