Availability and use of PET in patients with brain tumours - a European Organisation for Research and Treatment of Cancer - Brain Tumour Group (EORTC-BTG) survey

Purpose: Positron emission tomography (PET) is increasingly used in neuro-oncology. However, little is known about its application across European institutions and reasons for variable implementation. Methods: Between June and August 2024, members of the European Organisation for Research and Treatment of Cancer - Brain Tumour Group (EORTC-BTG) completed a cross-sectional online survey on PET use in neuro-oncological practice. Results: Overall, 103 replies from 20 countries were received. A PET facility was available at 96/103 (93.2%) sites, of whom 74 (77.1%) performed PET in patients with brain tumours. Reasons for not performing PET included limited availability of tracers (14/29, 48.3%), high cost (11/29, 37.9%), and PET perceived unnecessary (8/29, 27.6%). Of sites performing PET, 69/74 (93.2%) reported use in glioma, 58/74 (78.4%) in brain metastasis, 52/74 (70.3%) in meningioma, and 46/74 (62.2%) in CNS lymphoma. Amino acid PET was performed at 62/71 centres (87.3%; 3 not reported [n.r.]), most frequently in glioma (58/59, 98.3%, 3 n.r.) and for differentiation of treatment-related changes from tumour progression (58/59, 98.3%). Somatostatin receptor (SSTR) PET was performed at 50/68 sites (73.5%, 6 n.r.), mainly in meningioma (48/49, 98.0%), for patient selection before radioligand therapy (41/49, 83.7%) and for radiotherapy target volume definition (33/49, 67.3%). Unrestricted coverage by statutory health insurance was reported by 46/59 (78.0%) centres for amino acid PET and 33/49 (67.3%) for SSTR PET. Conclusion: PET use in neuro-oncology is variable across EORTC-BTG sites. Generation of evidence in clinical trials and surveys including non-academic institutions are needed to guide implementation in clinical practice.