Dynamic 18F-Fluoro-Ethyl-Tyrosine Positron Emission Tomography/ Computed Tomography: A Better Predictor of Isocitrate Dehydrogenase Mutation in Presurgical Evaluations of Glioma.

The recent WHO classification of gliomas has incorporated molecular markers such as isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion into the ambit of morphological diagnosis, and 18F-fluoro-ethyl-tyrosine (18F-FET) positron emission tomography (PET) has shown its utility in noninvasive glioma grading and prognosis. Both dynamic and static FET PET parameters may assist in predicting the IDH mutational status, but time to peak derived from dynamic data may be a better predictor for IDH status. We present a case of left frontal lobe lesion suggestive of high-grade glioma on magnetic resonance imaging and static 18F-FET PET images, however, dynamic FET image was suggestive of low-grade IDH1-mutated glioma which was later confirmed on histology and immunohistochemistry.