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Abstract #0864

Early Perfusion Changes in Patients with Recurrent Low-Grade Gliomas Treated with Everolimus (RAD001) Under a Phase II Clinical Trial

Michael Wahl1, Christopher Kazu Williams2, Janine Lupo2, Susan Chang3, Daphne Haas-Kogan1, Sarah Nelson2, 4

1Radiation Oncology, University of California, San Francisco, San Francisco, CA, United States; 2Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States; 3Neurosurgery, University of California, San Francisco, San Francisco, CA, United States; 4Bioengineering and Theraputic Sciences, University of California, San Francisco, San Francisco, CA, United States

Everolimus is an inhibitor of mTOR, a molecule in a signaling pathway activated in most low-grade gliomas and known to have angiogenic effects. In this phase II clinical trial, patients with recurrent low grade gliomas are treated with everolimus and followed with serial multimodal MRI while on treatment. We observe a significant decrease in DCE perfusion MRI parameters, including FBV (a measure of capillary density) and Kps (a measure of vascular permeability). This represents the first clinical demonstration of antiangiogenic effects of everolimus, and raises the possibility that perfusion parameters can be used as early markers of treatment response.

Keywords

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