[Becker's melanosis. Study of seven cases by photonic and electron microscopy. Contribution to the histogenesis of the cytoid bodies (author's transl)].

A survey of seven cases of Becker's melanosis has been performed. Their clinical characteristics are described. The photonic microscopy showed the basal layer overloaded with melanin, some alterations of the superficial dermis, and the appearance of cytoid bodies. The electron microscopy pointed out that the melanocytes showed some slight alterations, but were not more numerous. The keratinocytes were normal, without any kind of alteration, except for a melanin-overload. The dermis showed, in some places, an amorphous granular material replacing the normal collagen, and, yet, cytoid bodies. The location of these bodies was, most often, free in the dermis, but, very rarely, at the epidermal level. Moreover, they were seen steadily within the cytoplasm of the fibroblasts, without any limitating membrane. This is in favour of a fibroblastic origin of the cytoid bodies in Becker's malanosis, and, therefore, of some disturbances in the fibroblasts physiology. The results are discussed by comparison with the observations of cytoid bodies in various diseases and the appearance of these bodies within the cytoplasm of various cells: keratinocytes, fibroblasts, melanocytes, nervous cells, histiocytes. It is suggested that it is a very general cellular-degeneration phenomenon. We particularly emphazise the alterations of the dermis in Becker's melanosis.