COMPARISON OF COPLANAR AND NON- COPLANARVMAT FOR BRAIN CANCER BY USING THE DOSIMETRICAL AND RADIOBIOLOGICAL INDICES

Background: Recent techniques of radiotherapy such as volumetric modulated arc therapy (VMAT) that delivered in Coplanar technique or non-coplanar allows to deliver high doses the brain tumors, at same time reducing risk normal tissues compared with intensity (IMRT) and three-dimensional conformal (3D-CRT). Aim: The aim current work is compare dosimetrical radiobiological indices treatment plans for tumor using CO-VMAT NC-VMAT choose optimum treated cases. Patients methods: Twenty-one cases tumors were performed planning study. are planned by coplanar non VMAT optimized evaluate parameters related PTV dose coverage sparing organs risk. total 60 Gray 30 fractions during a single phase daily 2 Gray. Results: In calculations, gave similar (homogeneity index HI, modified homogeneity MHI, conformity CI quality factor QF) values PTV, while was higher (target TCI, prescription isodose target volume ratio PITV number CN) lower (gradient GI, gradient measure GM) values, Monitor units MUs values. equivalent uniform EUD control probability TCP complication free P+ large tissue NTCP less NC-VMAT. Conclusion: While previous studies showed used when far from risk, present found can be near (OARs) because it achieve OARs together. We strongly recommend should located inside able more them.