[A rare cause of cauda equina syndrome: primary epidural lymphoma]. / Une cause rare de syndrome de la queue de cheval: Le lymphome epidural primitif.

INTRODUCTION: Primary epidural lymphoma is generally manifested by isolated epidural involvement. On rare occasions it can lead to cauda equina syndrome. CASE: A 56-year-old man was hospitalized for lumbago, weakness in the legs and sphincter problems. A dorsolumbar MRI revealed that the anterior and posterior peridural space from D11 to L3 was filled by a mass compressing the marrow and compacting the roots. The L2 to L4 laminectomy revealed an extradural tissue leading to the diagnosis of large B-cell lymphoma. Metastatic workup demonstrated unremarkable findings. DISCUSSION: Primary epidural lymphoma accounts for less than 10% of epidural tumours and less than 1% of non-Hodgkin lymphomas. Its clinical manifestations are related to the tumoral process or involvement of medullar vessels. It can be, but rarely is, manifested by cauda equina syndrome. Diagnosis is based on histological analysis of tissue taken during the decompression laminectomy. Prognosis is relatively good.