Gliomas represent the most frequent primary brain tumor, with 2,500 to 3,000 new cases per year in France. Their diagnosis, although highly complex, is essential for determining patient management. While grade I gliomas (infrequent) are curable by surgery or present a slow progression, grades II to IV require heavy treatment (surgery and radio-chemotherapy), and are associated with a prognosis ranging from 10-15 years for grade II to only 15 months for glioblastoma. One of the key processes in glioma oncogenesis is the activation of a telomeric maintenance mechanism (TMM). Two TMMs ensure the maintenance of a telomere size compatible with intense cell proliferation (TERT mutation and ATRX loss). Liquid biopsy is used for the routine diagnosis and monitoring of treatment efficacy of different cancers. To date, no routine clinical testing of liquid biopsies is available for gliomas. The detection of glioma-specific oncogenic processes, by liquid biopsy, in peripheral blood (ctDNA) could improve diagnosis and follow-up and then avoid surgery for patients with suspected lesions. Three oncogenic markers can be used to detect gliomas: IDH mutation, TERT mutation, and a marker correlated with ATRX loss on total blood cells. We hypothesized that the circTeloDIAG will improve and accelerate the diagnostic/prognostic value of the actual classification and provide a new tool to manage patient response to treatment via liquid biopsy. It will combine detection of three markers in liquid biopsy, to produce a versatile tool for all types of gliomas. Patients with suspected newly diagnosed or recurrent glioma will be included.