The impact of dose calculation algorithm for SBRT lung cancer radiotherapy treatment

Introduction: The study aimed to provide the dose accuracy effects between Anisotropic Analytical algorithm (AAA) and the deterministic solver Acuros XB (AXB) that are available on Eclipse TPS (Varian Medical Systems, Palo Alto, CA) treatment planning system (TPS). The different is due to the electron transport difference in case of small fieldsMaterial and methods: For the study non-small cell lung cancer (NSCLC) patient CT scans are used to do retrospective SBRT plans via AAA and recalculated by AXB dose calculation algorithms using Eclipse treatment planning system. The main dosimetric comparison parameters are: Conformity index (CI), Homogeneity Index (HI), Gradient Index (GI), Target mean dose and calculation time. Results: Based on the results, the CI is (1.45±0.55) to (1.85±0.7). The HI are (0.15±0.07) and (0.13±0.08), the Gradient index GI for AAA were (4.8±2.6) and for AXB reaches to (7.4±3.8) and the maximum dose for PTV are differed about 2.3% to 4.5%, mean dose and the calculation time significant similar for AAA and AXB respectively.Conclusion: As the findings using the deterministic solver AXB in calculation for case of low density like lung cases is more accurate than AAA calculation Algorithm in SBRT treatment