[Cutaneous epitheliomas induced by ionizing radiation during radiotherapy. Presentation of 35 cases].

Thirty five cases of carcinomas of the skin, presumably induced by ionizing radiation therapy are reported. There was a precise topographic relationship between the site of irradiation and that of onset of tumor; in 31 cases, there were multiple neoplastic foci in the skin area exposed to ionizing radiation; a sufficiently long period of time had elapsed from the time of exposure to ionizing radiation to the clinical diagnosis of induced tumor; cases in which there were cutaneous carcinomas in other parts of the body as well as in the skin area exposed to the radiation were excluded from the series. Almost all patients had been subjected to ionizing radiation for treatment of benign diseases and 29 for arthrosis. The median age of the patients at the time of exposure to the ionizing radiation was 33,33 years. The radiation dose to which the patients had been subjected varied from 10 to 25 Gy; this dose is rather low, however it is in this dose range, according to Gray, a relatively high incidence of induced tumor is verified. The median interval between exposure to ionizing radiation and clinical finding of the tumor was 18.5 years. The carcinomas were observed almost always in the trunk and like spontaneous carcinomas at this site they were almost exclusively basal cell type.