Abstract
Radiation dose-tumor control response assays were presented for a fibrosarcoma and squamous-cell carcinoma, studied as transplants in (C3H/He x C57)-F1 hybrid mice. X radiation was administered either as a single dose or as 10 equal doses with 24-hr intervals between treatments; conditions at irradiation were either "hypoxia"; "air" or normal; or "O2 30 psi." Effectiveness of treatment administered in a single radiation dose was modified only slightly by respiration of O2 at 30 psi for 15 min. prior to treatment. However, for the fractionated irradiation, respiration of O2 at high pressure was markedly effective in increasing tumor cure probability. Results from these studies and from earlier studies on a C3H and a DBA mouse mammary carcinoma were reviewed.