A novel somatostatin-receptor (SSTR) targeting peptide—18F-SiTATE—has been shown to provide excellent imaging in patients with meningiomas, identifying bone involvement and lesions previously undetected on standard morphological imaging. 18F-SiTATE has a longer half-life and can be produced in large quantities by a cyclotron, which offers significant logistical advantages over the 68Ga-labeled ligands currently used in meningioma imaging. This research was presented at the Society of Nuclear Medicine and Molecular Imaging 2022 Annual Meeting.
Meningiomas account for nearly one-third of all brain tumors. Located in the primary central nervous system, most meningiomas are not cancerous, but can cause severe side effects, such as changes in vision, headaches and memory loss.
Eighty-six patients with known or suspected meningiomas undergoing 18F-SiTATE PET/CT were included in the study. Researchers evaluated uptake intensity of meningiomas, healthy organs, and non-meningioma lesions. Bone involvement of meningiomas was also assessed on PET and compared to morphological imaging (CT/MRI).
Uptake of 18F-SiTATE PET/CT was significantly higher in meningiomas compared to healthy organs and non-meningioma lesions. Overall, the scans identified 177 meningioma lesions and 41 non-meningioma lesions. Among the meningioma lesions, 27.1 percent were not clinically suspected and/or not detected on previous standard imaging. In addition, 51.1 percent of meningioma lesions showed partial bone involvement and 13.6 percent showed predominant bone involvement.
“This study shows that 18F-SiTATE PET/CT has a high feasibility for the detection of meningiomas, including bone involvement. This is especially important since bone involvement has major impact on surgery and radiotherapy planning for meningioma patients yet cannot be properly assessed using standard morphological imaging,” stated Marcus Unterrainer, MD, PhD, M.Sc., radiologist and nuclear medicine physician in the Department of Radiology at the University Hospital at Ludwig Maximilian University of Munich in Munich, Germany.
Researchers also noted that 18F-SiTATE has a longer half-life than 68Ga-DOTATATE and 68Ga-DOTATOC, radiopharmaceutical agents commonly used to image meningiomas. Combined with the potential for large-scale cyclotron production (as opposed to a reliance on 68Ga generators), 18F-SiTATE offers clinicians significant logistical advantages which could foster widespread use of SSTR-targeted imaging in neuro-oncology.
PHOTO CAPTION: A: Structural formula of 18F-SiTATE. B: Patient example of meningioma recurrence at the left sphenoid wing with extensive trans-osseous extension and strong SSTR-expression on 18F-SiTATE PET. C: Patient example with predominantly intraosseous tumor remnant at the frontal bone after several pre-treatments with strong SSTR-expression on 18F-SiTATE PET.
Abstract 864. “Next generation PET/CT imaging in meningioma – first clinical experiences using the novel SSTR-targeting peptide 18F-SiTATE.” Marcus Unterrainer, Department of Radiology, University Hospital, LMU Munich, Munich, Germany, and Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany; Lena M. Unterrainer, Sophie C. Kunte, Astrid Delker, Simon Lindner, Matthias Brendel, Adrien Holzgreve, Leonie Beyer, Peter Bartenstein and Nathalie L. Albert, Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany; Wolfgang G. Kunz, Clemens C. Cyran and Jens Ricke, Department of Radiology, University Hospital, LMU Munich, Munich, Germany; Klaus Jurkschat, Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Dortmund, Germany; Carmen Wängler, Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Mannheim, Germany; Björn Wängler, Molecular Imaging and Radiochemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Mannheim, Germany; Ralf Schirrmacher, Department of Oncology, Division of Oncological Imaging, University of Alberta, Edmonton, Alberta, Canada; Maximilian Niyazi Department of Neurosurgery, University Hospital, LMU Munich, Munich, Germany; and Joerg C. Tonn, Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany