Evaluation of Diagnostic Performances of 18F-FDOPA PET KInetics

Inclusion Criteria: * Age between 18 and 75 years old * WHO general condition ≤2 * Identification of a unifocal brain tumour at the initial diagnosis with no contrast in the MRI and suspected to be a LGG, with biopsy/surgery envisaged within 6 months of the PET scan * MRI performed a maximum of 3 weeks before inclusion and comprising the conventional morphological sequences (T1, T1 sequences with injection of contrast agent and T2 FLAIR). * Subject affiliated to or beneficiary of a social security plan * Subject having received complete information on the organisation of the research and having signed the informed consent form. Exclusion Criteria: * Multifocal brain lesions * Contraindication to 18F-FDOPA PET * Pregnant, parturient women or nursing mothers under Article L1121-5 * Women of childbearing age who do not have effective contraception under Article L1121-5 * Monitoring not possible * Persons deprived of their liberty by a judicial or administrative decision under Article 1121-8, persons undergoing psychiatric treatment under Articles L. 3212-1 and L. 3213-1. * Patients cannot simultaneously participate in an interventional research trial for the duration of the KING study