PET – Advancing Brain Tumor Imaging

Diffuse gliomas are malignant brain tumors that cannot be adequately investigated using traditional imaging techniques such as MRI. Glioma activity and spread can be better visualized using amino acid positron emission tomography. The first international criteria for standardized imaging of gliomas utilizing amino acid PET have now been established by an international research group (RANO Group) led by MedUni Vienna and LMU Munich. The Lancet Oncology released this ground-breaking research.

The RANO group has created new criteria for measuring the treatment response of diffuse gliomas, led by oncologist Matthias Preusser of the Medical University of Vienna and nuclear medicine specialist Nathalie Albert of LMU Munich. MedUni Vienna’s Tatjana-Traub Weidinger (Department of Radiology and Nuclear Medicine) and Maximilian Mair (Division of Oncology, Department of Medicine I) are also involved in the research.

Diffuse gliomas are malignant brain tumors that arise from glial cells in the brain. This type of tumor is usually aggressive and difficult to treat. The RANO group has developed criteria that enable the evaluation of treatment success using positron emission tomography. “These PET-based criteria, called PET RANO 1.0, open up new possibilities for the standardized assessment of diffuse gliomas,” says Preusser.

Standardized criteria for interpreting PET images for the first time

PET is an imaging technology that measures metabolic processes in the body using radioactively labeled chemicals. Amino acid PET is used to detect diffuse gliomas. Its tracer is a protein (amino acids) that accumulates in brain tumors.

Albert explains, “PET imaging with radioactively labeled amino acids has proven to be extremely valuable in neuro-oncology and enables reliable imaging of the activity and extent of gliomas. Amino acid PET has been used for years but has not yet been evaluated in a structured way. In contrast to MRI-based diagnostics, there were previously no criteria for interpreting these PET images.”

“These new criteria will enable researchers and physicians to use PET in clinical trials and clinical routine,” adds Preusser, “they are based on expert consensus and create a basis for future studies and the comparison of treatments for improved therapies.”

The RAO Working Group is a worldwide, multidisciplinary team tasked with developing new standardized response criteria for clinical trials in brain malignancies. For more than ten years, a group of specialists from diverse disciplines has been producing standard reference standards for the assessment of numerous clinically relevant elements.

For more information: Nathalie L Albert et al, PET-based response assessment criteria for diffuse gliomas (PET RANO 1.0): a report of the RANO group, The Lancet Oncology (2024). DOI: 10.1016/S1470-2045(23)00525-9