In standard care for patients diagnosed with a primary or secondary (metastasis) cerebral tumor, there is currently complex clinical situations in which the clinic and Magnetic Resonance Imagery (MRI) do not allow for the medical team to arrive at a conclusive diagnosis. The therapeutic proposition requires then a delay in additional follow-up of at least 3 months in order to clarify the situation, with a potential delay in diagnosis and therefore therapeutic care. The contribution of cerebral molecular imagery could allow for new additional information to be brought in or to increase the confidence index in the diagnosis in order to comfort the therapeutic collective attitude proposed in the multidisciplinary meeting (MM).