[Treatment technic and clinical dosimetry in whole-body irradiation]

At the Istituto Nazionale Tumori, Milan, total-body irradiation (TBI) is delivered by a 15 MV linear accelerator, with two lateral opposed beams. Maximum build-up at the skin is achieved by lateral slabs of perspex 3 cm thick. Attenuation filters or bolus are used for dose compensation, or reduction, to the head and lungs. The dose delivered to clinically relevant anatomic regions is determined by "in vivo" dosimetry. For this purpose, calibrated diodes are employed, which are positioned at the entrance and at the exit of the beams. "In vivo" dosimetry data show our TBI technique to allow an homogeneous irradiation of all body areas, with maximum deviation of the mean dose value from reference point dose of -11% in the posterior abdomen, at the spinal cord shielded by arms.