[Congenital nevus cell nevi of the skin--a nomenclatural and therapeutic problem].

The alarming increase in the incidence of malignant melanomas has caused interest to be focused on some of the precursors or tumor markers, such as dysplastic nevi or congenital nevocytic nevi. Both clinically and histologically, as well as by the incidence of malignancy, three groups of congenital nevocytic nevi may be distinguished. Small nevi (diameter less than 1.5 cm) are frequent, but it remains to be elucidated whether they involve an increased risk of malignancy. On the basis of differences in potential malignancy the larger congenital nevocytic nevi may be subdivided into two forms. Malignant melanomas occur more frequently and earlier in life in large nevi (diameter greater than 20 cm) compared with medium-sized nevi (diameter 1.5-20 cm). Medium-sized congenital nevi can usually be removed without considerable problems. In very large nevi, however, surgical treatment is more difficult. Since the risks involved in performing radical surgery in children may bear no relationship to possible benefits, repeated clinical examinations, detailed photographic documentation and immediate excision of any suspicious skin areas must be undertaken in such patients.