title: Localized hair follicle hamartoma.
abstract: A 4-year-old male presented with an indurated papular plaque on his right nasolabial fold. The lesion, present since the child was a few months of age, progressively extended in a band-like fashion up to the upper lip. Microscopically, there was almost complete replacement of the hair follicles by trichoepithelioma-like epithelial proliferations associated with hyperplastic sebaceous glands. We interpret this lesion as a localized form of the clinicopathological entity known as generalized hair follicle hamartoma.
authors.affiliation: 1st Clinic of Dermatology, University of Milan-IRCCS Ospedale Maggiore of Milan, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Alessi
authors.forename: A
authors.initials: A
authors.lastname: Azzolini
mesh_terms: D002455:Cell Division; D002675:Child, Preschool; D004848:Epithelium / Q000473:pathology; D006197:Hair / Q000473:pathology*; D006201:Hair Diseases / Q000175:diagnosis / Q000473:pathology*; D006222:Hamartoma / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D008297:Male; D012627:Sebaceous Glands / Q000473:pathology