Speaker
Description
Abstract
Background and Purpose: The lengthy treatment time of pencil beam scanning proton therapy (PBS-PT) limits its application for mobile tumors like liver cancer. This study aims to combine a high-efficiency beam transport system with spot reduction techniques to significantly shorten treatment time, enabling single breath-hold therapy.
Materials and Methods
We simulated three treatment plans for 12 liver cancer patients: conventional (Plan A), spot reduction only (Plan B), and a combined high-efficiency transport and spot reduction plan (Plan C). Our core innovation involved using BDsim to optimize beam transport, which increased the efficiency of low-energy beams (70 MeV) by 100 times, with parameters validated by TOPAS.
Results
Plan C was significantly superior to Plan A, reducing control points by 69.8% and energy layers by 53.5% (P<0.001), shortening the average single-field irradiation time to under 10 seconds. In contrast, Plan B showed no significant improvement. Plan C maintained dosimetric quality and robustness while boosting efficiency.
Conclusion
This study demonstrates that combining a high-efficiency beam transport system with spot reduction effectively addresses the challenge of long treatment times for mobile tumors, providing a crucial solution for the broader clinical adoption of PBS-PT.
Figure 1: Comparison of Single-Field Irradiation Times and Patient Target Volume Sizes
