title: Trichoepithelioma associated with cellular blue nevus.
abstract: BACKGROUND
  Epithelial elements, such as trichoepithelioma, are occasionally associated with melanocytic nevi.
  
  
  OBJECTIVE
  A case of trichoepithelioma in association with cellular blue nevus is reported.
  
  
  RESULTS
  A solitary, pigmented nodule was removed from the scalp of a middle-aged woman. Histopathologic examination demonstrated a circumscribed cellular blue nevus within which were embedded epithelial strands and cystic structures consistent with trichoepithelioma.
  
  
  CONCLUSIONS
  Trichoepitheliomas have been described in relation to common acquired nevi, but an association with a blue nevus is rare. The intimate admixture of trichoepithelioma within the nodule of a nevus supports the concept of epithelial induction by melanocytic nevi.
authors.affiliation: Department of Pathology, Vancouver Hospital and Health Sciences Centre, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: A M
authors.initials: AM
authors.lastname: Al-Ghamdi
authors.forename: M J
authors.initials: MJ
authors.lastname: Trotter
mesh_terms: D002277:Carcinoma / Q000150:complications* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D018329:Nevus, Blue / Q000150:complications* / Q000473:pathology / Q000601:surgery; D009508:Nevus, Pigmented / Q000150:complications* / Q000473:pathology / Q000601:surgery; D012536:Scalp Dermatoses / Q000150:complications* / Q000473:pathology / Q000601:surgery