Vice versa, highly F-FDG-avid lung lesions in patients with brain tumors should lead to distant metastases as differential diagnosis despite their rare occurrence.
The present study indicated that gadolinium-enhanced MRI combined with 18F-FDG PET/CT and laboratory examinations are helpful in distinguishing cerebral syphilitic gumma from brain tumors and infectious diseases, therefore avoiding unnecessary surgery.
O-(2-[<sup>18</sup>F]fluoroethyl)-L-tyrosine ([<sup>18</sup>F]FET) is the most promising radio-labeled amino acid tracer for brain tumor imaging due to the limitation of 2-deoxy-2-[<sup>18</sup>F]fluoro-D-glucose ([<sup>18</sup>F]FDG) and L-methyl-[<sup>11</sup>C]methionine (<sup>11</sup>C-MET).
The limitations of [<sup>18</sup>F]fluorodeoxyglucose ([<sup>18</sup>F]FDG), including producing false-positive or -negative results, low image contrast in brain tumor diagnosis and poor differentiation of tumor and inflammatory, necessitate the development of new radiopharmaceuticals.
The results support that [<sup>18</sup>F]FPDOPA seems to be a potential PET tracer for tumor imaging, especially be a better potential PET tracer than [<sup>18</sup>F]fluoro-2-deoxy-d-glucose ([<sup>18</sup>F]FDG) for brain tumor imaging.
A previous review published in 2012 demonstrated the role of clinical PET for diagnosis and management of brain tumors using mainly FDG, amino acid tracers, and <sup>18</sup>F-fluorothymidine.