A comparative study of the dosimetric impact on IMRT planning with VMAT plans using a varying number of arcs in prostate cancer

Abstract

Abstract A study has been carried out to explore the impact by varying the number of arcs and beam arrangement on dose distributions. For this volumetric modulated arc therapy and 7-field, intensity-modulated radiation therapy plans have use for prostate cancer cases. The eclipse treatment planning system version 13.6 (Varian California, USA) was used to assess dosimetry data for 20 patients. All patients received intensity-modulated radiation therapy and volumetric modulated arc therapy plans with a varying number of arcs. 6MV X-Ray photon beam energy uses for each patient. Statistical plan assessments have been carried out for various dosimetric parameters to evaluate execution efficiency. There were no statistically significant changes (p>0.05) observed in D98% dose coverage while D2%, conformity index, homogeneity index, monitor unit, and treatment delivery time were showing statistically significant changes (p<0.05). In contrast to six arc volumetric modulated arc therapy and 7 field-intensity-modulated radiation therapy plans, Single arc volumetric modulated arc therapy plans showed 23.28 % and 25.96 % less monitor unit, 97.52 % and 137.53 % less treatment delivery time. It concluded that using a higher number of arcs in volumetric modulated arc therapy plans for prostate cancer improves plan efficiency. The four arc volumetric modulated arc therapy plans appeared to provide a reasonable trade-off between enhanced treatment delivery time and high treatment plan quality.