[The PET scan in neuro-oncology--indications, differential diagnosis and clinical application]

Results of 157 PET (positron emission tomography) studies in 102 patients with known or presumed intracranial (ic.) tumors are reviewed. In 106 studies [18F]-2-fluoro-2-deoxy-D-glucose (FDG) and in 51 cases [11C]-methionine (MET) was used as the PET tracer. CT and MRI imaging accompanied the PET studies in each case. Results of pre- and/or postoperative studies are compared. PET was concluded to have a fundamental role in the precise differential diagnosis in case of ic. space-occupying pathologies since it is capable of providing information that is not obtainable or may be equivocal based solely on CT and/or MRI investigations. However, it is also mandatory to be aware of the limits of PET.