THE treatment of epithelioma of the skin by roentgen rays and radium is influenced by the accessibility of the growth to irradiation, by its radiosensitivity (as contrasted with the radioresistance of the normal tissues included in the irradiated field) and, finally, by the dosage and the technic of radiotherapy.
Ninety-eight per cent of the basal cell and 75 per cent of the squamous cell epitheliomas of the skin are located on the head or neck, while 2 per cent of the basal cell and 25 per cent of the squamous cell cancers are found on the trunk and extremities. Basal cell epitheliomas, usually grow slowly, often remain flat and show central excavation, and, except in certain locations, they rarely invade subjacent tissues and do not metastasize to regional nodes. Squamous cell epitheliomas are more likely to proliferate without undergoing necrosis, to form bulky growths or to invade
LENZ M. RADIOTHERAPY OF EPITHELIOMA OF THE SKIN. Arch Derm Syphilol. 1946;53(6):588–596. doi:10.1001/archderm.1946.01510350028006