Comprehensive Study between calculated and Measured DVHs for Prostate Cancer Patients Using IMRT/RapidArc Dosimetric Techniques

The objectiveof this workis to compare betweenthe calculated dose by treatment planning system (TPS) and the measured dose collected by ArcCHECK phantom,for prostate cancer patients with two techniques:Volumetric Modulated Arc Therapy (VMAT) and Intensity Modulated Radiation Therapy (IMRT) using 3DVH system (Sun Nuclear Corporation, Melbourne, FL, USA). ArcCHECK is a 3D dosimetry quality assurance (QA)toolusedto measure the doses that are calculated by a (TPS)and compares them with the measured dose from the linear accelerator. The 3DVH is a measured dose(QA) software application used for comparing 3D dose and dose volume histograms (DVHs). One dataset is imported as a reference dose plan by(TPS), and the other is calculated by 3DVH from a correction of the intended TPS dose plan by ray tracing corrections that have been determined with a measurement system. 3DVH analysis uses the dose errors (derived from the measured versus calculated doses in phantom) to perturb the original 3D planned dose and accurately estimate the 3D dose distribution. This method that called PDP (Planned Dose Perturbation) results in fast, accurate, and powerful DVH comparisons.We evaluated dose difference between the TPS calculations and the collected dose reconstructed by 3DVH software.