Brain chemical clues may predict who lives longer with aggressive cancer

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Patients, between 18 and 88 years, with glioblastoma (histologically proven) in first relapse after conventional treatment by surgery and temozolomide and radiotherapy * Biological Criteria * Polymorphonuclear neutrophils\> 1500 / mm3 * Plates\> 100,000 / mm3 * SGOT-SGPT \<5 at the upper limit of normal (ULN) * Bilirubin \<1.5 x ULN * Creatinine \<1.5 LSN and creatinine clearance * Proteinuria \<1 g / 24 hours * Patient with health insurance * Consent signed by the patient if he is lucid, or failing that by the person of trust Exclusion Criteria: * Patients who can not benefit from bevacizumab for the following reasons: * Symptomatic cerebral or tumor hemorrhage * Karnofsky Index less than 50% or * Patients already treated with an antiangiogenic molecule or Gliadel (diagnosis and recurrence). * Coagulation disorders in case of injectable treatment (especially for avastin), * Contraindications known to the MRI: Pace Makers, foreign bodies intraocular, electrodes ... * Uncontrolled severe concomitant pathology, including another evolving cancer (with the exception of operative cutaneous tumors, in situ cancer of the cervix or breast treated). * Uncontrolled Infection * Uncontrolled hypertension (PAS\> 160 mm Hg) despite optimized treatment * Coronary artery disease or unstable arterial disease. Evolutionary aneurysm. * Myocardial infarction dating from less than 6 months. * Peripheral arterial or cerebrovascular accident occurring less than 6 months. * Heart Failure\> grade II NYHA * Hemorrhagic Disease (Hemophilia, Willebrandt ...) * Nephrotic syndrome with proteinuria\> 2 g / 24 h * History of haemoptysis dating less than 1 month. * Pulmonary embolism dating less than 1 month. * Surgical intervention (other than craniotomy or stereotactic biopsy) dating less than one month or essential and predictable surgery. * History of digestive fistula or intestinal perforation with resolution less than 6 months. * Hypersensitivity to bevacizumab or to any of the excipients mentioned in Composition. * Hypersensitivity to Chinese hamster ovary (CHO) cells or to other human or humanized recombinant antibodies. * Severe Myelosuppression * Pregnant or nursing. Contraception should be prescribed if necessary during treatment. * Persons deprived of liberty or placed under safeguard of justice (guardianship or curatorship), * Subject involved in another search including an exclusion period still in progress at pre-inclusion * Patient refusing to participate in the study