Malignant melanoma with evidence of maturation arising from a giant congenital nevocellular nevus.

The association between melanoma and giant congenital nevocellular nevus has been well documented, although controversy still exists regarding the precise incidence. The following patient report illustrates the excision of malignant melanoma arising from a giant congenital nevocellular nevus in a 4-month-old infant. The child had malignant melanoma with deep dermal involvement diagnosed by incisional biopsy with positive margins. She underwent subsequent en bloc resection of the original biopsy site and nevus. The reexcision specimen showed no evidence of malignancy. No adjuvant chemotherapy was used. The child is disease free at 5 years. It is possible that very young children (infants) with melanoma arising in a giant congenital nevocellular nevus may have a good prognosis.