• brain tumors;
  • minibeam radiation therapy;
  • preclinical trials

This feasibility work assesses the therapeutic effectiveness of minibeam radiation therapy, a new synchrotron radiotherapy technique. In this new approach the irradiation is performed on 9L gliosarcoma-bearing rats with arrays of parallel beams of width 500–700 µm. Two irradiation configurations were compared: a lateral unidirectional irradiation and two orthogonal arrays interlacing at the target. A dose escalation study was performed. A factor of three gain in the mean survival time obtained for some animals paves the way for further exploration of the different possibilities of this technique and its further optimization.