Radiosensitization of C3H mouse mammary tumours using fractionated doses of X rays with the drug Ro-07–0582

Abstract Three fractionated X-ray schedules were used, with and without the electron-affinic radiosensitizer of hypoxic cells, Ro-07–0582, to determine the local control of first-generation transplants of spontaneous mammary tumours in C3H mice. Three or five fractions were given in either four or nine days overall time. The results were compared with acute skin reactions in other mice caused by the same treatment schedules. For a given skin reaction, the local control of tumours varied widely, from good to bad, when different X-ray only schedules were used. All three schedules using Ro-07–0582 however yielded good results. It appears that the use of the hypoxic-cell radiosensitizer took the unreliability out of these short fractionated treatments.