Becker's nevus syndrome: case report.

Becker's nevus is a hyperpigmented macula that is predominantly located on the anterior trunk or on the scapular region, frequently associated with hypertrichosis. The association of Becker's nevus with other cutaneous, musculoskeletal or maxillofacial anomalies has been called Becker's nevus syndrome. We report a case of a 16-year-old girl with a hyperpigmented macula which spread from her right anterolateral trunk to the inner part of her right thigh accompanied by ipsilateral mammary hypoplasia. The skin lesion started when the patient was seven years old when it was also noticed ipsilateral mammary hypoplasia. The histological exam confirmed the clinical hypothesis of Becker's nevus.