Inclusion Criteria:  Adult patient aged ≥ 18, no age limit A signed informed consent obtained before any study specific procedures Patient affiliated to a French social security system Patient ability to understand experimental procedures Patient able to speak, read and understand French  Also for the "Low-grade glioma" group, the following inclusion criteria applies:  - Brain surgery for a suspected low-grade tumor, histologically confirmed on tumor sample  Also for the "High-grade glioma" group, the following inclusion criteria applies:  - Brain surgery for a suspected high-grade glioma, histologically confirmed on tumor sample  Also for the "Control group, the following inclusion criteria applies:  - Brain surgery for a non-tumor disease (cavernoma, arteriovenous malformation)  Exclusion Criteria:  Legal incapacity or physical, psychological social or geographical status interfering with the patient's ability to sign the informed consent or to terminate the study Pregnant and/or breastfeeding women (this will be checked in declarative way) Patients with medical history of cancer other than the brain tumor, whatever the treatment received  Also, for the "Low-grade glioma" group, the following exclusion criteria applies:  Previous chemotherapy or radiation therapy for the low-grade glioma (but previous surgery/ies is/are allowed) No indication for chemotherapy for 6 month after surgery  Also, for the "High-grade glioma" group, the following exclusion criteria applies:  - Previous chemotherapy or radiation therapy for the glioma  Also, for the "control" group, the following exclusion criteria applies:  - Diagnosis or suspicion of primary or secondary brain tumor