Quantitative models of low-grade glioma: from the laws of infiltration in diffuse gliomas to a model of radiotherapy
C. Deroulers, Univ Paris Diderot, France; M. Badoual, Univ Paris Diderot, France; C. Gerin, CNRS, France; B. Grammaticos, CNRS, France; J. Pallud, Sainte Anne Hospital, Paris, France; P. Varlet, Sainte Anne Hospital, France
In diffuse gliomas, infiltration of apparently healthy tissues surrounding zones which appear as abnormal on the MRI is thought to be one of the main causes of treatment failure. Therefore, having accurate mathematical models of this phenomenon may be a key to therapeutic advances. WHO Grade II gliomas (GIIG), although ultimately lethal in most cases, are a good starting point to achieve this goal since they lack more complicated features such as neoangiogenesis, allowing one to concentrate on models with only a few parameters.
Using a combination of computer simulations and approximate analytical computations, we give results about the extension of infiltrating cells in the ideal case (but inspired by some in vitro experiments) where proliferation is negligible. Then we discuss a more realistic model of grade-II glioma (GIIG) where tumour cells migrate and proliferate, and induce the host tissue to produce ``edema'', which we argue is the cause of the MRI signal abnormality, rather than the tumour cells themselves. The model is compared to data coming from biopsy samples of GIIG. Finally, we use it to discuss the outcome of radiotherapy on a series of patients.Format: Oral communication