Cancer cells implanted in a skin region previously exposed to an erythema dose of x-rays show a series of degenerative changes in every way comparable to the frequently described stages of cancer cell degeneration following x-ray treatment. The findings contrast strongly with the survival and growth of grafts implanted in unexposed regions in the same animal. Since the changes are the same whether the cancer cells have been directly exposed in situ or merely implanted in the previously exposed skin, it follows that it is impossible to establish microscopically a direct injury from the x-raying as the principal factor in the therapeutic action of x-rays on cancer.

This content is only available as a PDF.