Congenital melanocytic nevi

© 2015 John Wiley & Sons, Ltd. All rights reserved. Congenital melanocytic naevi (CMN) are benign pigmented naevi present at birth. The incidence ranges from 1 to 2% overall to approximately 1 in 20 000 for naevi projected to be greater than 20 cm in diameter in adulthood. CMN can present as isolated singular lesions or can be accompanied by a variable number of other CMN. Neurological abnormalities, in particular intraparenchymal melanosis, are the most common complication of CMN. Recently, the term congenital melanocytic naevus syndrome has been proposed to characterize the association between CMN, extracutaneous features such as neurological abnormalities and/or the typical facies of many affected children. The overall incidence of malignant melanoma in patients with CMN is approximately 1%, with an increased risk in patients with CMN > 40 cm and satellite lesions at birth. Surgery with current techniques has not been proven to alter the risk of malignancy and thus should only be routinely considered for aesthetic improvement.