[Histology of dermabrasion in giant nevi].

Three female infants suffering from nevocytic giant nevi (GNi) of lumbosacral location were treated by means of high-r.p.m. dermabrasion. In the follow-up period up to 26 months, the GNi completely healed, and there were no recurrences. Before and immediately following dermabrasion as well as after complete healing without any irritation, we took biopsies from the affected areas for histological examination. By way of dermabrasion, we removed the pigmented nevus cell-tissue with its focal arrangement in the upper corium. In the depth of the dermis, however, reaching down to the subcutaneous tissue, there were widespread nevus cells left together with single hair follicles and sweat glands. In the course of healing, we observed the formation of a scar camouflaging the remaining nevus, but sharply demarcated from it, and showing no junctional activity. The clinical healing of the three nevocytic GNi went without junctional activity which usually indicates possible cancerization as mode of development associated with these malformations in the dermo-epidermal border line. Thus dermabrasion might reduce the risk for melanoma. There is still left some risk coming from the remaining nevus cell formations in the depth of the dermis or the proliferating cutaneous appendages that may induce junctional activity.