The Association between Chronic Radiation Damage of the Hair Follicles and Tumor Formation in the Rat

Chronic follicle damage has been studied after single exposures to graded doses of electrons at various depths of penetration by the use of whole mounts of rat skin. Chronic radiation-induced follicle damage is manifest by complete loss of follicles as well as by various grades of follicle atrophy. In the non-ulcerogenic dose range, the dose-incidence curves for atrophic follicles and tumors are remarkably similar, and the ratio of tumors to atrophic follicles is 1/2000 to 1/4000. Evidence is presented which indicates that the induction of chronic hair follicle damage is an important factor in the formation of epithelial skin tumors.