Becker's nevus syndrome

Becker's nevus (BN) is a unilateral hyperpigmented, often hairy, cutaneous hamartoma, with geographic borders. It is usually localized on the shoulder , anterior chest, scapula, or upper arm, but there have been reports of BN in other areas (eg, lower extremities, face). In most cases, the lesion app ears in late childhood or adolescence, and both congenital and familial cas es have been described.