title: Differentiation between cerebellopontine angle tumors in cancer patients.
abstract: OBJECTIVE
  The possibility of metastasis to the cerebellopontine angle should be considered when a cancer patient has inner ear-related symptoms, although such metastasis is rare. Distinguishing between an independent tumor and a metastasis presents a challenge to the clinician once magnetic resonance imaging reveals a space-occupying lesion in the cerebellopontine angle. This study attempted to differentiate between primary benign and metastatic malignant cerebellopontine angle tumors in cancer patients.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  A total of 174 cancer patients with inner ear-related symptoms such as vertigo, hearing loss, or tinnitus were seen at the university hospital from January 1994 to December 2000. All patients underwent a battery of audiologic and neurotologic tests. Magnetic resonance imaging was performed either when the clinical presentation suggested vertigo of central origin or when sensorineural hearing loss developed.
  
  
  RESULTS
  Magnetic resonance imaging confirmed tumors of the cerebellopontine angle in 6 (3%) of the 174 patients, including 3 men and 3 women. Their ages ranged from 46 to 80 years (mean 62 years). The final diagnoses were breast cancer with cerebellopontine angle metastasis (1), breast cancer with cerebellopontine angle epidermoid cyst (1), colon cancer with cerebellopontine angle metastasis (1), colon cancer with acoustic neuroma (1), nasopharyngeal carcinoma with cerebellopontine angle metastasis (1), and nasopharyngeal carcinoma with cerebellopontine angle benign tumor (1).
  
  
  CONCLUSIONS
  When a cerebellopontine angle tumor is discovered in a cancer patient, metastatic cancer should be suspected when the tumor presents with deficits of the VIIth and VIIIth cranial nerves of rapid progression or bilateral involvement, or extracranial systemic metastasis. Laboratory examinations such as cytologic study of the cerebrospinal fluid and serologic study can assist in the diagnosis.
authors.affiliation: Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan.
authors.forename: Tsung-Wei
authors.initials: TW
authors.lastname: Huang
authors.forename: Yi-Ho
authors.initials: YH
authors.lastname: Young
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000175:diagnosis; D002528:Cerebellar Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D002530:Cerebellopontine Angle / Q000473:pathology; D003110:Colonic Neoplasms / Q000175:diagnosis; D003937:Diagnosis, Differential; D004814:Epidermal Cyst / Q000175:diagnosis; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008575:Meniere Disease / Q000175:diagnosis / Q000209:etiology*; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis; D009464:Neuroma, Acoustic / Q000175:diagnosis; D014012:Tinnitus / Q000209:etiology*