Francois Bidault MD, Presenter: Nothing to Disclose

Thibault De La Motte Rouge, Abstract Co-Author: Nothing to Disclose

Mohamed Sahnoun, Abstract Co-Author: Nothing to Disclose

Vanessa Rousseau, Abstract Co-Author: Nothing to Disclose

Agnes Laplanche, Abstract Co-Author: Nothing to Disclose

Frédéric Dhermain, Abstract Co-Author: Nothing to Disclose

Denis Ducreux, Abstract Co-Author: Nothing to Disclose

Caroline Caramella MD, Abstract Co-Author: Nothing to Disclose

Sandra Paola Canale MD, Abstract Co-Author: Nothing to Disclose

Corinne Balleyguier MD, Abstract Co-Author: Nothing to Disclose

Julien Domont, Abstract Co-Author: Nothing to Disclose

Christophe Massard, Abstract Co-Author: Nothing to Disclose

Clarisse Dromain, Abstract Co-Author: Nothing to Disclose

High grade gliomas are tumors with a poor prognosis. Bevacizumab (Bvz) is commonly employed for treatment of recurrence or is currently being evaluated (depending on country). Bvz is known to alter imaging contrast enhancement that is sometime difficult to be interpreted. DSC-MRI can be used to measure cerebral blood volume (CBV) and vascular permeability and can be employed with widely used MR sequences and software. The goal of this study was to assess CBV and permeability as potentially biomarkers for survival at baseline and after treatment with Bvz.

Retrospective study. Twenty-five patients with recurrent high grade glioma treated with Bvz, were evaluated with DCS-MR at baseline and after treatment. Corticosteroids treatment was noted. All MRI examinations were reviewed by two radiologists reaching consensus about OMS size criteria, qualitative alterations, and quantitative functional criteria: CBV, permeability, calculated with DCS-MR sequence and DPTools software (free available software). Statistical analysis compared actuarial survival with baseline and post Bvz fMR (Kaplan Meier curves).

Survival was not statistically related to baseline or post Bvz CBV or permeability (Logrank test: p>5%). There was no significant relationship between corticosteroid dose and vascular permeability at baseline (Spearman test: p>5%). The permeability values significantly decrease after Bvz (median=85%). Survival was not related to initial tumor size but was significantly decreased if the tumor progressed during Bvz treatment (Logrank test: p=0.011).

CBV and vascular permeability measured by DSC-MRI were not efficient biomarkers of survival in our study. This study confirms the ability of DSC-MRI to demonstrate impact of Bvz on tumor vascular permeability. Our study did not find a significant effect of corticosteroid dose on vascular permeability in these recurrent tumors. Tumor size progression in size remains an indicator of poor prognosis. Further studies are necessary to determine the role of DSC-MRI for the prognostication of gliomas and to match results with 2010 RANO criterias.

Results to be shared with radiologists interested in glioma and in different ways to reach CBV/permeability data. Poor effect of corticosteroid on permeability may have an interest for further studies

Bidault, F, De La Motte Rouge, T, Sahnoun, M, Rousseau, V, Laplanche, A, Dhermain, F, Ducreux, D, Caramella, C, Canale, S, Balleyguier, C, Domont, J, Massard, C, Dromain, C, High-Grade Gliomas Treated with Bevacizumab: Assessment of Tumor Response with Dynamic Susceptibility Contrast Perfusion MRI (DSC-MRI).  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11009457.html