title: Primary melanocytic tumor of the cerebellopontine angle mimicking a vestibular schwannoma: case report.
abstract: OBJECTIVE
  The majority of tumors of the cerebellopontine angle (CPA) are benign. We report the case of a primary malignant melanoma of the CPA that mimicked a vestibular schwannoma (acoustic neuroma). We discuss the differential diagnosis and prognosis of melanotic lesions at this location.
  
  
  METHODS
  A 49-year-old man presented with a 7-year history of unilateral deafness and a several month history of imbalance, intractable nausea and vomiting, as well as weight loss. A neurological work-up revealed a large tumor in the left CPA radiographically diagnosed as a vestibular schwannoma.
  
  
  METHODS
  A translabyrinthine approach revealed a pigmented, vascular neoplasm encasing vessels and cranial nerves of the left CPA. The tumor was subtotally resected, and a histopathological diagnosis of melanoma was made. The patient had no history of cutaneous melanoma and no other site of disease was ever discovered.
  
  
  CONCLUSIONS
  This case most likely represents primary melanoma of the central nervous system that mimicked a vestibular schwannoma. The differential diagnosis of melanotic lesions of the CPA is discussed as are the prognostic implications of each diagnosis.
authors.affiliation: Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, Minnesota 55901, USA.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Piedra
authors.forename: Bernd W
authors.initials: BW
authors.lastname: Scheithauer
authors.forename: Colin L W
authors.initials: CL
authors.lastname: Driscoll
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Link
mesh_terms: D002528:Cerebellar Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery / Q000628:therapy; D002530:Cerebellopontine Angle; D017024:Chemotherapy, Adjuvant; D003937:Diagnosis, Differential; D017809:Fatal Outcome; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008544:Melanocytes / Q000473:pathology*; D008545:Melanoma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery / Q000628:therapy; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000175:diagnosis*; D019635:Neurosurgical Procedures / Q000009:adverse effects; D018714:Radiotherapy, Adjuvant; D014057:Tomography, X-Ray Computed