title: The clinical appearance of clonal nevi (inverted type A nevi).
abstract: BACKGROUND
  The term "clonal nevus" is used to describe a variant of melanocytic nevus that histologically exhibits a localized proliferation of pigmented epithelioid dermal melanocytes within an otherwise ordinary nevus (Ball NJ, Golitz LE. Melanocytic nevi with focal atypical epithelioid cell components: a review of seventy-three cases. J Am Acad Dermatol 1994; 30: 724-729). Reports to date have focused on the histologic appearance of these lesions.
  
  
  OBJECTIVE
  To characterize the clinical appearance of clonal nevi.
  
  
  METHODS
  Clinical and histologic examinations were performed of a single clonal nevus from each of five patients (two men and three women; age range, 37-80 years).
  
  
  RESULTS
  All nevi were round to oval in shape with smooth, well-defined borders. They were uniformly tan to light brown in color, except for a single blue-gray to blue-black focus of hyperpigmentation. The diameters of the nevi ranged from 2.5 to 10 mm. In individual nevi, the hyperpigmented focus was either centrally or eccentrically located and measured 1-2 mm in diameter. Histologically, these lesions showed banal melanocytes associated with a localized proliferation of melanocytes with abundant pigmented cytoplasm in the dermis, admixed with melanophages.
  
  
  CONCLUSIONS
  The appearance of clonal nevi--tan with a focus of blue-gray to blue-black pigmentation--allows one to recognize the lesion clinically.
authors.affiliation: Department of Dermatology at Wayne State University, Detroit, Michigan, USA.
authors.forename: Phung M
authors.initials: PM
authors.lastname: Huynh
authors.forename: Earl J
authors.initials: EJ
authors.lastname: Glusac
authors.forename: Jean L
authors.initials: JL
authors.lastname: Bolognia
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D049109:Cell Proliferation; D003593:Cytoplasm / Q000648:ultrastructure; D015622:Epithelioid Cells / Q000473:pathology; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000473:pathology; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008875:Middle Aged; D009506:Nevus / Q000473:pathology; D018330:Nevus, Intradermal / Q000473:pathology; D009508:Nevus, Pigmented / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology*