A novel four dimensional, patient specific simulation model of solid
tumor response to chemotherapeutic treatment in vivo is presented. The special case of
glioblastoma multiforme treated by
temozolomide is addressed as a simulation paradigm. The model is based on the patient's imaging, histopathologic and genetic data. For a given
drug administration schedule Iying within acceptable toxicity boundaries, the concentration of the
prodrug and its metabolites within the
tumor is calculated as a function of time based on the
drug phramacokinetics. A discretization mesh is superimposed upon the anatomical region of interest and within each geometrical cell of the mesh the most prominent
biological "laws" are applied. The
biological cell fates are predicted based on the
drug pharmacodynamics. The outcome of the simulation is a prediction of the spatiotemporal activity of the entire
tumor and is virtual reality visualized. A good qualitative agreement of the model's predictions with clinical experience has strengthened the applicability of the approach. Long term clinical and quantitative adaptation and validation as well as modeling the normal tissue reactions are in progress. The proposed model primarily aims at providing a reliable platform for performing patient individualized in silico experiments as a means of chemotherapeutic treatment optimization.