[Histochemical and ultrastructural study of cytochrome-oxydase in basal cell epithelioma]

The activity of cytochrome-oxydase is less pronounced in the basal cell epithelioma than in the basal cells of the surrounding normal epidermis. The electron microscopic study of the localisation of the enzyme reveals that the cells of the basal cell epithelioma contain two types of mitochondria, the first of which having the same size as the epidermal mitochondria, and the other being giant mitochondria. The latter seem to be less active. The weak reactivity of the basal cell epithelioma for cytochrome-oxydase is probably due to the reduction of the cristae in mitochondria and to the functional deficiency of the giant mitochondria.