Nuclear medicine societies issue guidelines for PET imaging of gliomas

The Society of Nuclear Medicine and Molecular Imaging (SNMMI), the European Association of Nuclear Medicine (EANM), the European Association of Neurooncology (EANO), and the working group for Response Assessment in Neurooncology with PET (PET-RANO) have issued joint practice guidelines for positron emission tomography (PET) imaging with specific radiotracers and radiolabeled amino acids. Published in the March issue of the European Journal of Nuclear Medicine and Molecular Imaging, the guidelines are intended to help promote the appropriate use of PET imaging and contribute to evidence-based medicine that may help improve the diagnostic impact of this imaging procedure in neurooncological practice. They supersede guidelines published in 2006.

Gliomas represent approximately 80% of all malignant central nervous system (CNS) tumors and are the second-most common primary brain tumor, according to the societies. Although magnetic resonance imaging (MRI) is the primary imaging modality used for primary evaluation, pre- and postsurgical imaging, radiotherapy planning and surveillance during treatment, and monitoring for recurrence, the modality has limitations, say the authors. The study authors state that MRI contrast enhancement can be unreliable as a surrogate for tumor size or growth, and can be influenced by therapeutics that affect tumor vascular permeability. PET is increasingly being used to supplement MRI in the clinical management of gliomas.

The guidelines specify the radiotracers and dose for adult and pediatric patients and specific imaging protocols. They discuss standardized uptake value calculations and analysis for both static and dynamic PET image acquisition. Recommendations for interpretation and the contents of the report are detailed. A detailed list of known pitfalls and estimated occurrence of false-positive presentation in amino acid PET and 18-F-fluorodeoxyglucose (¹⁸F-FDG) PET is included. Topics also include quality control and radiation safety.

“Since the previous EANM guidelines in 2006, the clinical use of molecular imaging with PET and PET/CT in the diagnosis of glioma has continuously increased in Europe and the U.S.,” wrote the authors. “This document attempts to provide some guidance on the performance and interpretation of molecular imaging to supplement recent clinical guidelines [from the Neuro-Oncology Working Group and European Association for Neuro-Oncology], and to bring PET brain imaging into daily clinical practice and into larger scale interinstitutional clinical neurooncological trials across imaging platforms.”

REFERENCES

1. Albert NL, Weller M, Suchorska B, et al. Response Assessment in Neuro-Oncology Working Group and European Association for Neuro-Oncology recommendations for the clinical use of PET imaging in gliomas. Neuro Oncol. 2016;18:1199–208.
2. Law I, Albert NL, Arbizu J, et al. Joint EANM/EANO/RANO practice guidelines/SNMMI procedure standards for imaging of gliomas using PET with radiolabelled amino acids and [¹⁸F] FDG: version 1.0. Eur J Nucl Med Mol Imaging. 2019;46(3):540-557.