title: Hair follicle nevus in a 2-year old.
abstract: We report a 2-year-old boy with an elastic soft, flatly elevated, skin-colored nodule on his nasal ala. Histologic examination revealed numerous small hair follicles in several stages of maturation in the dermis. Serial sections did not show any cartilage or a central epithelial lined cystic structure. Based on clinico-pathologic findings, we diagnosed this lesion as a hair follicle nevus. Hair follicle nevus is quite rare. Histologically, it is very important not to find cartilage or a central epithelial lined cystic structure for distinction from an accessory auricle and from a trichofolliculoma, respectively. Awareness of the clinical and pathologic characterization of hair follicle nevus is an aid to a correct diagnosis.
authors.affiliation: Department of Dermatology, Gunma University Graduate School of Medicine, Gunma, Japan. smotegi@showa.gunma-u.ac.jp
authors.forename: Sei-ichiro
authors.initials: S
authors.lastname: Motegi
authors.forename: Hiroo
authors.initials: H
authors.lastname: Amano
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tamura
authors.forename: Osamu
authors.initials: O
authors.lastname: Ishikawa
mesh_terms: D001707:Biopsy, Needle; D002675:Child, Preschool; D005500:Follow-Up Studies; D018859:Hair Follicle / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009506:Nevus / Q000175:diagnosis / Q000473:pathology*; D009666:Nose; D035583:Rare Diseases; D018570:Risk Assessment; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology*