title: Atypical central nervous system lymphoma at the cranial base: report of four cases.
abstract: OBJECTIVE
  Primary central nervous system lymphoma is a disease with increasing incidence. Atypical presentations are becoming more frequent.
  
  
  METHODS
  Three patients bearing cavernous sinus lesions presented initially with periorbital pain and diplopia. Tolosa-Hunt syndrome was the initial presumptive diagnosis for two patients, and meningioma was the diagnosis for the third patient. A fourth patient presented with left ear pain, and a mass in the left internal auditory canal was thought to represent an acoustic neuroma.
  
  
  METHODS
  For all four patients, an operative pathological diagnosis was obtained and was compatible with central nervous system lymphoma. All patients were treated with osmotic blood-brain barrier disruption with intra-arterial chemotherapy using a methotrexate-based regimen.
  
  
  CONCLUSIONS
  All four cases included atypical presentations of lymphoma. These cases again illustrate that a correct diagnosis cannot be obtained based only on imaging and clinical findings.
authors.affiliation: Department of Diagnostic Radiology, Oregon Health Sciences University, Portland 97201, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Roman-Goldstein
authors.forename: A
authors.initials: A
authors.lastname: Jones
authors.forename: J B
authors.initials: JB
authors.lastname: Delashaw
authors.forename: S
authors.initials: S
authors.lastname: McMenomey
authors.forename: E A
authors.initials: EA
authors.lastname: Neuwelt
mesh_terms: D000328:Adult; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000627:therapeutic use; D001812:Blood-Brain Barrier; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000378:metabolism; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007269:Injections, Intra-Arterial; D008223:Lymphoma / Q000175:diagnosis* / Q000188:drug therapy / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage / Q000627:therapeutic use; D008875:Middle Aged; D019291:Skull Base
chemical_list: D000964:Antimetabolites, Antineoplastic; D008727:Methotrexate