Study on the dosimetric effect of respiratory motion on boron neutron capture therapy for lung cancer

However, respiratory motion has a critical impact on the dose accuracy in BNCT treatment of lung cancer. [Purpose]: This study aims to quantify the dosimetric impact caused by respiratory motion during BNCT treatment of lung cancer. [Methods]: This study employs the Monte Carlo simulation method to develop a dynamic model capturing the spatiotemporal variations of tumors and organs due to respiratory motion in lung cancer treatment, and performs Monte Carlo dose calculations for BNCT.

Firstly, using the Multi-function And Generalized Intelligent Code-bench based on Monte Carlo method (MagicMC), this study modeled the adult male phantom provided by Oak Ridge National Laboratory (ORNL). Then, by incorporating high-order cosine functions that describe respiratory motion, this study established a dynamic dose calculation model. Finally, this study employed MagicMC to calculate the dose errors in tumors and organs resulting from respiratory motion in different directions within three-dimensional space. [Results]: The results indicate that during a respiratory cycle, the tumor in all three motion directions exhibits the largest percentage dose difference at the 50% phase.