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Purpose:To investigate a Hybrid IMRT/VMAT technique which combines intensity modulated radiation therapy(IMRT)and volumetric modulated arc therapy(VMAT)for the treatment of non-small cell lung cancer(NSCLC).Materials and methods:2 partial arcs VMAT,5-field IMRT and Hybrid IMRT/VMAT plans were created for 15 patients with NSCLC.The Hybrid IMRT/VMAT plans were combination of 2 partial arcs VMAT and 5-field IMRT.The dose distribution of planning target volume(PTV)and organs at risk(OARs)for Hybrid IMRT/VMAT was compared with IMRT and VMAT.The monitor units(MUs)and treatment delivery time were also evaluated.Results:Hybrid IMRT/VMAT significantly improved the target conformity and homogeneity compared with IMRT and VMAT.The V30 of normal lung for hybrid plans was significantly lower than IMRT plans(17.7%vs 18.7%; p<0.05)and VMAT plans(17.7%vs 18.4%; p<0.05).The V5,V10,V30 and mean lung dose(MLD)of normal lung for hybrid plans were 5.1%,7.7%,3.8%and 3.9%lower than those for VMAT plans,respectively(p<0.05).The maximum dose of spinal cord for hybrid plans was 5.6 Gy lower than that for IMRT plans(p<0.05).The dose received by esophagus and heart for hybrid plans were significantly lower than those for IMRT plans.The mean delivery time of IMRT,VMAT and hybrid plans were 280 s,114 s,and 327 s,respectively.The mean MUs needed for IMRT,VMAT and hybrid plans were 933,512,and 737,respectively.Conclusions:The Hybrid IMRT/VMAT technique significantly improved the target conformity and homogeneity compared with IMRT and VMAT.It reduced V5,V10,V30 and MLD of normal lung compared with VMAT,and spared the OARs better with fewer MUs compared with IMRT.Hybrid IMRT/VMAT technique can be a viable radiotherapy technique with better plan quality.