[Grafts of human skin containing nevi or superficial nevocarcinoma onto athymic nu/nu mice: macroscopic and microscopic studies].

17 thin grafts of corpse skin containing neavi, were grafted onto the back of athymic mice. All the grafts took. The naevi were than deeply incised on 3 occasions. No evidence of abnormal healing, of pigment release, or of malignant transformation, appeared. 10 epidermal grafts of superficial malignant melanoma, taken from 4 different patients, took successfully. In 7 of these, superficial ulcerations appeared but were definitively re-epithelialised from the adjacent Mouse skin. 5 and 7 months later, the melanoma are stable, without local extensions, infiltration or apparent metastase. Despite the absence of an inflammatory reaction, these melanoma are paradoxically quiescent in nude Mice.