title: A purely extradural lumbar nerve root cavernoma mimicking acute myeloid leukemia recurrence: Case report and literature review.
abstract: BACKGROUND
  Myeloid sarcoma (MS) is a malignant tumor that usually occurs concomitantly with or following acute myeloid leukemia (AML). Cavernomas are benign congenital malformations that are unusual in the spine and exceedingly rare in pure extradural locations.
  
  
  METHODS
  We report a 73-year-old female with a previous medical history of AML in remission for 3 years who presented with symptoms of low back pain and right lower extremity radiculopathy. A magnetic resonance scan showed an extradural, foraminal lesion centered at the L2 level involving the right L2 nerve root. In view of the history of AML, this lesion was potentially considered MS, a form of AML relapse. Surgery consisting of a right L1 and L2 hemilaminectomy facilitated gross total resection of the purely extradural lesion the proved histologically to be a cavernoma.
  
  
  CONCLUSIONS
  In patients with a history of leukemia, MS must be considered in the differential diagnosis for any epidural or nerve root lesion that appears following treatment. Although rare, cavernomas must be considered among the differential diagnoses for epidural nerve root lesions in the setting of AML.
authors.affiliation: Department of Neurosurgery, Centro Hospitalar Lisboa Norte, Lisbon, Portugal.
authors.forename: Edson
authors.initials: E
authors.lastname: Oliveira
authors.affiliation: Department of Neurosurgery, Centro Hospitalar Lisboa Norte, Lisbon, Portugal.
authors.forename: José Pedro
authors.initials: JP
authors.lastname: Lavrador
authors.affiliation: Department of Neurosurgery, Centro Hospitalar Lisboa Norte, Lisbon, Portugal.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Teixeira
authors.affiliation: Department of Pathology, Centro Hospitalar Lisboa Norte, Lisbon, Portugal.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Pignatelli
authors.affiliation: Department of Neurosurgery, Centro Hospitalar Lisboa Norte, Lisbon, Portugal.
authors.forename: Sérgio
authors.initials: S
authors.lastname: Livraghi
keywords: Acute myeloid leukemia; extradural cavernoma; lumbar nerve root; lumbar spine; myeloid sarcoma