title: Primary meningeal T-cell lymphoma at the clivus mimicking a meningioma.
abstract: BACKGROUND
  Most primary lymphomas of the central nervous system (CNS) are of B-cell origin and are found intra-axially, with a few reported cases of skull base tumors involving the upper clivus or sellar region or both. In this case, a tumor resembling a clivus meningioma without osseous involvement was surgically removed and turned out to be a primary T-cell lymphoma.
  
  
  METHODS
  A 60-year-old woman presented with slight right-sided abducens nerve palsy. Cranial imaging revealed an extra-axial mass at the caudal clivus resembling a meningioma. The tumor was removed surgically; smear preparations obtained intraoperatively were inconclusive presumably because of preoperative steroid treatment. The final diagnosis was peripheral T-cell lymphoma, not otherwise unspecified. The patient developed a secondary meningiosis supposedly caused by surgery.
  
  
  CONCLUSIONS
  Although a very rare entity among primary T-cell lymphomas of the CNS, these tumors also can occur as skull base lesions without involvement of the bone. Preoperative steroid medication may complicate intraoperative histologic assessment and lead to inadequate treatment of these tumors.
authors.affiliation: Department of Neurosurgery, Klinikum Grosshadern, Munich, Germany. stefan.grau@med.uni-muenchen.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Grau
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schueller
authors.forename: Carolin
authors.initials: C
authors.lastname: Weiss
authors.forename: Jörg-Christian
authors.initials: JC
authors.lastname: Tonn
mesh_terms: D003388:Cranial Fossa, Posterior / Q000473:pathology / Q000601:surgery*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D015192:Infratentorial Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D016399:Lymphoma, T-Cell / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008577:Meningeal Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008579:Meningioma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D019292:Skull Base Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery