title: Squamous cell carcinoma arising in a linear epidermal nevus.
abstract: An isolated, pruritic lesion developed in the right breast of a 17-year-old girl during a period of four months. The lesion was well circumscribed, erythematous, indurated, and markedly hyperkeratotic in the center. The histologic diagnosis was well-differentiated squamous cell carcinoma arising in a linear epidermal nevus. The development of squamous cell carcinoma in a linear epidermal nevus is a rare event, previously reported only in long-standing, extensive lesions of middle-aged to elderly patients. This case seems to be unique in regard to the patient's young age, the short duration of the nevus, and the lack of identifiable predisposing factors.
mesh_terms: D000293:Adolescent; D001943:Breast Neoplasms / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D003937:Diagnosis, Differential; D004817:Epidermis / Q000473:pathology; D005260:Female; D006801:Humans; D009378:Neoplasms, Multiple Primary / Q000473:pathology*; D009506:Nevus / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology*