Hybaroxic Radiation Therapy in Cancer Management

Abstract

Radiobiologically, the basis of hybaroxic radiotherapy is biophysical. The anoxia of the vascular supply of cancer overgrowth results in relatively radioresistant, anoxic, but viable cancer cells. The anoxia can be overcome by hybaroxia, and radiosensitivity may be restored. Hyperoxygenation of normally oxygenated tissue does not increase its radioresponsiveness. The application of hybaroxic radiotherapy in a modern radiotherapy institution requires no special radiation sources, little modification of facilities, and a reasonable amount of training of personnel. As one proceeds in the clinical application of this tool in radiation therapy of cancer, it becomes important to remember that hybaroxia restores the radiosensitivity of anoxic cells and protects nothing. Hybaroxic radiotherapy demands the same attention to radiation responsiveness of all tissues of the patient as do all forms of radiation therapy. Despite the remarkable improvement in the therapeutic ratio which can be expected by this new method, the radiobiologic effect on the intervening and adjacent tissues cannot be ignored.