Misdiagnosis of prepubertal malignant melanoma. Reclassification of a cancer registry material

Twenty cases of malignant melanoma of the skin occurring in children under 14 years of age were recorded by the Finnish Cancer Registry during the years 1954–63. Seventeen of these cases were histologically reclassified as follows: spindle and/or epithelioid cell nevus, 9; malignant melanoma, 2; cellular blue nevus, 2; compound nevus, 2; malignant tumors other than melanoma, 2. Four of the benign melanotic tumors were originally diagnosed as “juvenile melanomas.” The false connotation of malignancy inherent in this term is shown by the registration of these cases as malignant melanomas. The differential diagnostic criteria of Allen and Spitz1 were followed in calssification and the result showed a good agreement with the follow-up data.