Primary spinal lymphoma of the cauda equine is a very rare lesion that usually occurs in the brain tissue. The disease is classified as primary if there was no evidence of systemic lymphoma by screening at the time of diagnosis.

we report a case of a 75-year- old previously healthy man presented with leg weakness and urinary incontinence since 3 months. Neurological examination revealed a cauda equina syndrome. Spinal magnetic resonance imaging (MRI) revealed after intravenous contrast injection a homogenous enhancement (multiple lesions) in dura matter and in the filum terminalis. Brain, cervical and thoracic MRI did not reveal any mass. A biopsy of the lumbar dura was performed after a lumbar laminectomy and revealed a malignant lymphoma.

Primary spinal lymphoma of the cauda equina is a rare lesion with no specific laboratory or radiologic findings: only the anatomopathologic exam confirmed the diagnosis. Prognosis is poor despite aggressive treatment with radiotherapy, chimiotherapy or combination of them.