A case of malignant melanoma developed from giant congenital pigmented nevus in a seven year old girl was reported.
Since the identification of benign juvenile melanoma, the distinct rarity of true cutaneous malignant melanoma in infants and children has become generally recognized.
In giant congenital pigmented nevus, the malignant melanoma as a rule arises deep in the dermis.
In this case, the histopathologic finding shows no junctional activity in epidermodermal juction other than ordinary. nevocellular nevi, but some nevus cell nests and mild inflammatory cell infiltration in the upper dermis.
And in the deep dermis, well marginated but not encapsulated huge tumor mass, in which variable sized, pleomorphic, several vigorous mitotic figures in predominantly cuboidal cells and bizarre giant cells, which was thought to be developed from giant congenital pigmented nevus.
The few recorded cases of fatal cutaneous malignant melanoma in early life are of two types: those arising in giant congenital pigmented nevi and ordinary small nevi, de novo including; small nevus. The former account for between 22?0" and 40% of the total. This case is one of the reported 20 cases in the world.
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