Task 3: Modeling of tumor and dose delivery process during treatment via numerical simulations

The post-doc fellow Eric Garrido has started working in April 2014 with Nicolas Boussion.

This task aimed at developping two complementary tools:

1. A numerical model of the state-of-the-art TrueBeam (VARIAN) linear accelerator for external radiotherapy, as it has recently been acquired by the University Hospital of Brest.

2. A numerical model of tumor at two different scales, the voxel level, and the population of cells level. This model aims at simulating a tumor through its cells' population characteristics with parameters input from both morphological and functional imaging and radiobiology.

Once these two simulation tools will be operational, we will have the ability to compute highly realistic simulations of personalized external radiotherapy treatments by introducing real multimodal images of a patient within the simulation framework combining the LINAC model and the multiscale tumor model.

Modeling of the LINAC has been carried out within the GATE (Geant4 Application for Tomography Emission) framework, including the moving multi-leaf collimators and on-board real-time portal imaging. The most important development was the modeling and simulation of virtual source (phasespace) for the "patient-independant" part of the LINAC model to significantly reduce both the required disk storage space and computation times associated with it. Both dose delivery and integrated real-time portal imaging can be now simulated.

A C code is now operational to simulate the cells cycle and response to external dose deposition within a voxel, and to simulate population evolution within each voxel of a numerical tumor model. Parameters from both radiobiology and inputs from imaging still need more work and optimization.

The next step will be the actual combination of an anthropomorphic phantom or patients multimodal images with the tumor evolution model within the simulation framework of GATE and the LINAC model.

There are no communications or publications associated with this task yet. A technical note on the development on the LINAC source modeling is being written and scheduled to be submitted to Phys Med Biol in the next few months.