Hypofractionated irradiation of the solid form of Ehrlich ascites carcinoma in mice by a thin scanning proton beam

The dynamics of the growth of Ehrlich ascites carcinoma in mice of the SHK line exposed to hypofractionated high-dose irradiation by a thin scanning proton beam has been analyzed for different irradiation volumes and different time intervals (from 4 to 24 hours) between two 30-Gy fractions. Irradiation of the gross tumor volume and the planned target volume was performed within the Bragg peak; the energy of protons at the outlet of the accelerator ranged from 85 to 100 MeV. Hypofractionated irradiation of the gross tumor volume of Ehrlich ascites carcinoma resulted in a more pronounced antitumor effect than the irradiation of the planned target volume. The effect did not depend on the interval between the irradiation episodes.