Giant Pigmented Nevus
An irregular dark brown to black plaque over at least 5% of the body surface
represents a gaint pigmented nevus. Often the lesions are of such size as
to cover the entire trunk (bathing trunk nevi). Histologically, they are compound
nevi. Transformation to malignant melanoma has been reported in as many as
10% of cases in some series, although the true incidence is probably much
lower. Malignant change may occur in the neonatal period or at any time thereafter.