title: Narcolepsy secondary to fourth ventricular subependymoma.
abstract: BACKGROUND
  Secondary (symptomatic) narcolepsy is rare. We report a subependymoma of the fourth ventricle associated with narcolepsy. The patient was a 50-year old woman with a long history of narcolepsy who died of colonic carcinoma with no cerebral metastasis. She was positive for HLA-DR2. At autopsy there was a tumour dorsal to the fourth ventricle which involved the midbrain tectum and rostral pons. Histologic examination of the tumour confirmed it to be a subependymoma.
  
  
  METHODS
  Review of the previous cases of secondary narcolepsy was made with particular reference to the anatomical location of the lesions.
  
  
  RESULTS
  Most of the lesions were found around the third ventricle and rostral brainstem.
  
  
  CONCLUSIONS
  Knowing the anatomical localization of the pathological changes in secondary narcolepsy could be important in improving our understanding of its pathogenesis.
authors.affiliation: Division of Pathology, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada.
authors.forename: T K
authors.initials: TK
authors.lastname: Ma
authors.forename: L C
authors.initials: LC
authors.lastname: Ang
authors.forename: M
authors.initials: M
authors.lastname: Mamelak
authors.forename: S J
authors.initials: SJ
authors.lastname: Kish
authors.forename: B
authors.initials: B
authors.lastname: Young
authors.forename: A J
authors.initials: AJ
authors.lastname: Lewis
mesh_terms: D002551:Cerebral Ventricle Neoplasms / Q000150:complications* / Q000473:pathology; D005260:Female; D018315:Glioma, Subependymal / Q000150:complications* / Q000473:pathology; D015802:HLA-DR2 Antigen / Q000276:immunology; D006801:Humans; D008875:Middle Aged; D009290:Narcolepsy / Q000209:etiology* / Q000473:pathology
chemical_list: D015802:HLA-DR2 Antigen