Il trattamento dei tumori cerebrali in regime di ipofrazionamento accelerato della dose mediante tecniche cinetiche complanari non stereotassiche

In Radiotherapy the Accelerated hypofractionation of the dose is less investigated than other fractionation schedules. However its application on small brain tumors and brain metastases, through stereotactic radiosurgery obtains in comparable oncological situations better results than conventional treatments. Accelerated hypofractionation also improves the efficiency of the radiotherapy departments. Since 1994 the clinical use on brain tumors of the Polycentric Multiple Arc technique started on. This technique allows us to reproduce dose distributions similar to those of the brachiterapy treatments with linear sources (inhomogeneous dose that increases inside the tumor and that quickly decreases outside the target) This technique allowed accelerated hypofractionated schedules also in the treatment of large and very large tumors. In this presentation we describe the possibility to reproduce and to ameliorate the main characteristics of the PMA technique using either IMRT or IMAT techniques through: a better conformation of the geometry of the dose distribution to the geometry of the target; a simplified control of the set-up of the treatment; a simplified planning of complex treatments (IP). Some examples of clinical application are discussed.