This combined nevus on the abdomen of a 21-year-old man is composed of a Clark nevus in the upper part and a blue nevus in the lower part

This congenital combined nevus is characterized by a second hyperpigmented population of melanocytes/nevus cells within an otherwise ordinary congenital nevus. Some colleagues prefer to call lesions like this “congenital nevi with two cell populations”. The crucial aspect of this lesion, however, is not to overlook a melanoma evolving within a congenital nevus