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Background: To compare volumetric modulated arc therapy (VMAT) with conventional step and shoot intensity modulated radiation therapy (s-IMRT) in nasopharyngeal carcinoma (NPC)patients, and identify which T category patient gains the maximum benefit from VMAT.Methods: Fifty-two patients that randomly selected from 205 patients received VMAT at a single center were retrospectively replanned with s-IMRT.For a fair comparison, the planning target volume (PTV) coverage of the 2 plans was normalized to the same level.A standard planning constraint set was used;the constraints for the organs at risk (OARs) were individually adapted.The calculated doses to the PTV and OARs were compared for s-IMT and VMAT plans generated using the Monaco treatment planning system.Results: VM AT and s-IMRT plans had similar PTV coverage and OAR sparing within all T categories.However, in stratified analysis, VMAT plans lead to better or similar sparing of the OARs in early T category patients;and lead to poorer sparing of the OARs in advanced T category patients (P<0.05).VMAT shows significant advantages for low dose burden (P<0.05) compared with s-IMRT.The delivery time per fraction for VMAT (424±64 s) was shorter than s-IMRT (778 ± 126 s, p<0.01).Conclusions: VMAT provides similar dose coverage of the PTVs and similar/better normal tissue sparing in early T category NPC, and poorer OARs sparing in advanced T category NPC.And VMAT shows significant advantages for low dose burden and delivery time.