THE COMPLEMENTARY POTENTIALITIES OF POSITRON EMISSION TOMOGRAPHY IN THE PRIMARY DIAGNOSIS OF BRAIN TUMORS
Positron emission tomography (PET) is a noninvasive method to study pathophysiology and biochemistry of brain tumors. This functional information helps to assess structural brain changes detected with conventional magnetic resonance imaging and provides critical information for the patient management. The advantages and limitation of the tumor imaging with available in Russia radiotracers such as 2-[<sup>18</sup>F]-fluoro-2-deoxy-D-glucose ([<sup>18</sup>F]-FDG) and L-[<sup>11</sup>C]-methyl-methionine ([<sup>11</sup>C]-methionine) are discussed with particular emphasis on the biological background and mechanisms of the tumor uptake. The uptake of [<sup>11</sup>C]-methionine by tumors is greater than that by intact brain tissue, making [<sup>11</sup>C]-methionine «tracer of choice» in PET imaging in neurooncology. This review focuses on the role of PET with [<sup>11</sup>C]-methionine in the primary tumor diagnosis, identification of the glioma type and grade of malignancy, prognosis, glioma extent delineation as well as biopsy planning. In patients with suspected brain tumor the possible diagnostic challenges of structural neuroimaging are reviewed in details and common clinical indications for PET are present