Recent updates and plan in Geant4 based particle therapy system simulation framework

Particle therapy system simulation framework, PTSIM, is a simulation framework based on Geant4 Monte Carlo simulation. It has been developed in the project, “Development of simulation framework for advanced radiotherapy”, funded by the Japan Science and Technology Agency (JST) in the program of Core Research for Evolutional Research and Technology (CREST), from 2003 to 2010. The PTSIM has provided a common platform to model proton and ion therapy facilities, allowing users who are not Geant4 experts to accurately and efficiently run Geant4 simulations with the pre-build configurations. Efforts on further development of PTSIM are still under way to include more functionality and improve the performance. The PTSIM has been upgraded with the extensions in the DICOM-RT interface to coordinate with hospital information system, the Web interface with universal grid environment, etc. In this paper, we report on our activities about these updates and plan for extending the PTSIM functionality with new requirements from users.