The relationship between melanocytic nevi and malignant melanoma.

In conclusion, although there are data, some quite convincingly implicating dysplastic nevi and congenital nevi (particularly "giant") as "precursors" of malignant melanomas, our ability to predict the magnitude of these associations is lacking. Thus, until additional basic and clinical research data are forthcoming, any recommendation to prophylactically remove all congenital nevi or all dysplastic nevi in order to decrease the incidence of malignant melanoma is premature. In regard to congenital nevi, evidence exists that giant (larger than 20 cm in diameter) congenital nevi may have a significant risk factor so as to warrant, when feasible, prophylactic excision of such lesions. In our opinion, no uniform recommendation can be made at this time for the management of small and medium-sized congenital nevi. Patients with familial dysplastic nevus syndrome should be followed carefully and educated concerning the early detection of malignant melanoma. Patients with sporadic dysplastic nevus syndrome deserve further study to enable us to accurately determine their risk of developing malignant melanoma.