The aim of this study is to establish the diagnostic value of O-(2-[18F]-fluoroethyl)-L-tyrosine (FET) PET-CT, [18F]-fluorocholine (FCH) and magnetic resonance imaging (MRI) combined with magnetic resonance spectroscopy (MRS) in patients with suspected cerebral glioma using neuronavigated biopsies with histopathological analysis as reference.

The objectives of the study are:

• To demonstrate if the multimodal approach, combining the morphological aspect of the MRI with the metabolic aspect of the tumor with magnetic resonance spectroscopy (MRS) and O-(2-[18F]-fluoroethyl)-L-tyrosine (FET) or 18F]-fluorocholine (FCH) PET/CTthe FCH allows to improve the location of a active metabolic tumor and its impact on the ideal choice of sampling biopsy.
• To underline the differences and similarities between MRS and 18F]-fluorocholine PET / CT in the assessment of metabolism of the choline. To establish the diagnosis value of both methods, separately and in combination.
• To determine which examinations are useful and complementary for the diagnosis and the management of gliomes.

FET combined with MRS may be a powerful, widely applicable new method to improve the diagnosis of cerebral gliomas. The extent to which FCH and MRS provide similar information is not known precisely and this study will establish their respective diagnostic value in differentiating tumoral from non-tumoral tissue.

Inclusion Criteria:

• Suspicion of intracerebral glioma on MR
• Men of women
• Age >18, no upper limit as long as a biopsy or intervention is foreseen

Exclusion Criteria:

• Need of rapid intervention in <2 weeks
• Previous neurosurgical intervention (biopsy, shunt, etc.) or any other cerebral treatment

Patients with glioma suspicion referred for biopsy to our university hospital