The Radiation Biology of the Cutaneous Glands

THE radiobiologic characteristics of the glands of the skin have a practical as well as a theoretical interest. Practically, they are important in the treatment of hyperidrosis and acne. The theoretical importance they may have—a subject to which we shall confine ourselves—will be taken up in detail in this paper. Our present knowledge of this subject is best presented by a repetition of the views of the following research workers in radiation biology. Regaud and Lacassagne1 summarize their views on this subject as follows: “If the irradiation has been intensive and of an intensity sufficient to cause death of the epidermis, or has even exceeded this dose, then the hair follicles and the dermal glands are destroyed.” According to the views of these authors, the sebaceous and sweat glands are of equal radiosensitivity, and are as sensitive as the epidermis. On the other hand, Holthusen2 expressed the opinion: “The radiosensitivity of the appendages of the skin is somewhat greater than that of the epidermis.” According to this view, the cutaneous glands have a greater radiosensitivity than that of the epidermis and, therefore, the radiosensitivity of the sweat glands is about the same as that of the sebaceous glands. In contrast to this view, Schinz and Slotopolsky,3 on the basis of some theoretical considerations, expressed the opinion that the sebaceous glands (and the hair follicles) “are to be regarded as the most radiosensitive structures in the skin,” and they admit that “very little is positively known about the radiation biologic characteristics of the sebaceous glands.” It is apparent from the foregoing that the views in regard to the sensitivity of the different structures of the skin are not in harmony any more than are the views concerning the sensitivity of the cutaneous glands, as they are contradictory in some of the essential points. There are many reasons for this state of affairs. The number of anatomical studies which have appeared during the forty years of radiology which deal with the changes produced in the glands of the skin by radiation are very few in number. This may well be due to the fact that the changes in the cutaneous glands are of less interest and importance than, for example, those in the vessels, because changes in the latter are of far greater clinical importance than are the changes that may ensue in either the sebaceous or the sweat glands. And, insofar as the anatomical studies on the cutaneous glands as affected by irradiation, there is no definite ground of comparison between them, because either the experimental animals used were such that direct comparisons could not be made, or else only one of the various glands in the skin was the subject of the investigation.