[Traumatically induced junctional activity of nevocellular nevi (author's transl)].

Forty papillomatous nevi, mainly with junctional nests, were partially removed surgically in such a way that a small margin was left intact on one side and the deep nevus cells were retained on the flor of the wound. After healing of the wound, a small layer of scar tissue separated the regenerated epidermis from the deep nevus cells, which were left in the dermis. After very differing intervals, as early as 30 days after the partial surgical removal, typical alterations could be observed in the epidermis above the cicatrical tissue. Most frequently, there was a hyperpigmentation with an increase in the number of basal fluorescing dendritic cells, which could also be found along the uppermost parts of epidermal appendages. Moreover, nest-like conglomerations of pigment-producing cells appeared in the form of junctional nevus cell nests. About 2-3 month after the partial surgical removal "Abtropfung" was visible, indicating a regeneration of the nevus. Fluorescence-histochemical and enzyme-histochemical results revealed that marked alterations can be found not only in the newly formed epidermis above the scar, which morphologically show minor alterations.