Study design: A case report and clinical discussion.
Objective: To describe the diagnosis, pathophysiology, and treatment of a papillary renal cell carcinoma that developed an intradural spinal mass with cauda equina infiltration.
Summary of background data: Cancers that metastasize intradurally to the spinal canal are uncommon, accounting for the 6% of all spinal metastases. Those from renal cell carcinoma are especially unusual. Only 3 reports that describe the spread of metastatic renal cell carcinoma to the cauda equina have been published to our knowledge.
Methods: A female patient had undergone nephrectomy for the treatment of the papillary renal cell carcinoma 2 years before, and only 1 localization (at the genital tract) was previously diagnosed. The patient presented with lower back pain irradiated to both legs, vesical incontinence, and severe paraparesis.
Results: Preoperative magnetic resonance images of the lumbar spine showed an intradural spinal mass from L3-L5 with infiltration of the cauda equina; the lesion measured 62 mm craniocaudally and 16 mm anteroposteriorly, and thus occupied the majority of the intrathecal space at that level. The magnetic resonance images, surgical treatment, and related pathophysiology are reviewed.
Conclusions: The majority of cauda equina tumors are primary tumors, and metastases are very rare. To our knowledge, this is the fourth case described of metastasis of renal cell carcinoma at the cauda equina and the first of papillary type.