New onset headache caused by histiocytic sarcoma of the spinal cord and leptomeninges: a case report.

BACKGROUND: Headache due to raised intracranial pressure is rarely caused by spinal lesions. We describe a patient with primary histiocytic sarcoma who presented with a new onset headache with features of raised intracranial pressure and subtle signs of cauda equina syndrome due to predominant lower spinal cord infiltration and minimal intracranial involvement. CASE: A previously well 54-year-old man presented with a 2-month history of new onset headache with features of raised intracranial pressure. Progression of lower limb weakness was delayed and mild with diagnostic delay resulting from the primary presentation with headache leading to an initial focus on cerebral pathology. Subsequent investigations revealed a previously unreported presentation of primary histiocytic sarcoma infiltrating the cauda equina causing raised intracranial pressure headache. CONCLUSION: This case highlights the importance of a broad search in the investigation of new onset raised intracranial pressure headache, including imaging of the lower spinal cord. Primary histiocytic sarcoma should be considered in the differential diagnosis of this rare syndrome.