title: Amino Acid PET - An Imaging Option to Identify Treatment Response, Posttherapeutic Effects, and Tumor Recurrence?
abstract: Routine diagnostics and treatment monitoring in patients with primary and secondary brain tumors is usually based on contrast-enhanced standard MRI. However, the capacity of standard MRI to differentiate neoplastic tissue from non-specific posttreatment effects may be limited particularly after therapeutic interventions such as radio- and/or chemotherapy or newer treatment options, e.g., immune therapy. Metabolic imaging using PET may provide relevant additional information on tumor metabolism, which allows a more accurate diagnosis especially in clinically equivocal situations, particularly when radiolabeled amino acids are used. Amino acid PET allows a sensitive monitoring of a response to various treatment options, the early detection of tumor recurrence, and an improved differentiation of tumor recurrence from posttherapeutic effects. In the past, this method had only limited availability due to the use of PET tracers with a short half-life, e.g., C-11. In recent years, however, novel amino acid PET tracers labeled with positron emitters with a longer half-life (F-18) have been developed and clinically validated, which allow a more efficient and cost-effective application. These developments and the well-documented diagnostic performance of PET using radiolabeled amino acids suggest that its application continues to spread and that this technique may be available as a routine diagnostic tool for several indications in the field of neuro-oncology.
authors: Department of Neurology, University of Cologne, Cologne, Germany; Institute of Neuroscience and Medicine, Forschungszentrum Jülich, Jülich, Germany; Center of Integrated Oncology (CIO), University of Cologne, Cologne, Germany.
authors: Norbert
authors: N
authors: Galldiks
authors: Institute of Neuroscience and Medicine, Forschungszentrum Jülich, Jülich, Germany; Department of Nuclear Medicine, University of Aachen, Aachen, Germany.
authors: Karl-Josef
authors: KJ
authors: Langen
keywords: FDOPA PET; FET PET; MET PET; pseudoprogression; pseudoresponse; radiation necrosis; radiolabeled amino acids