TOPAS Monte Carlo and Eclipse Treatment Planning System Validation*

Various algorithms are employed in radiotherapy (RT) to compute the dosage. The accuracy of the calculated dose in RT is crucial for ensuring agreement with the delivered dose. The objective is to prioritize the accuracy of algorithms that directly influence the clinical results of patients. We aim to compare photon beam simulation between ARIA - Eclipse TPS (Varian Medical Systems, Palo Alto, CA, USA) and TOPAS MC (Tool for Particle Simulation, Monte Carlo). We aim to incorporate Monte Carlo simulations into our teaching methodology. Therefore, we must accurately define the simulation parameters to effectively compare our findings with the clinical calculations conducted at the Department of Medical and Radiation Oncology at Zilina Hospital. Monte Carlo simulations of ionizing radiation transmission from the source to the patient provide a simplified fundamental comprehension of radiotherapy. This study presents a comparative analysis percentual depth doses. The results indicate that comparing TOPAS MC and Eclipse TPS produces positive outcomes. TOPAS MC can accurately replicate the needed scenarios, ensuring they align with clinical outcomes. The results indicate that the TOPAS MC program may be helpful in the teaching process for simulating ionizing radiation.