Diagnostic performance of [18F]FDG PET/CT in large vessel vasculitis management: an umbrella review.

Large vessel vasculitis (LVV), encompassing giant cell arteritis (GCA), Takayasu arteritis (TAK) and polymyalgia rheumatica (PMR), is a significant cause of morbidity due to its inflammatory effects on large arteries. Accurate diagnosis is critical but challenging with conventional methods like biopsy or CT/MRI. This umbrella review evaluates the diagnostic performance of [18F]FDG PET/CT, a non-invasive imaging tool for assessing inflammation, in LVV management. A comprehensive search was conducted in PubMed/MEDLINE, Embase, Cochrane Library, Scopus, and Web of Science for systematic reviews and meta-analyses published up to February 2025, addressing the research question: "What is the role of [18F]FDG PET/CT in large vessel vasculitis?". Data extraction and quality assessment were performed independently by two reviewers using the Oxford Center for Evidence-Based Medicine criteria. Thirteen systematic reviews met the inclusion criteria, demonstrating high sensitivity (75.9-90%) and specificity (71-98%) of [18F]FDG PET/CT in detecting active LVV, particularly in GCA and TAK. It outperformed CT/MRI in identifying extracranial inflammation and showed promise in treatment monitoring. [18F]FDG PET/CT is a valuable tool for LVV diagnosis, offering high accuracy and clinical utility. However, emerging technologies such as LAFOV scanners and novel radiotracers, along with advancements in MRI techniques for intracranial assessment, define the new frontiers of diagnostic precision. Its integration into practice may enhance diagnostic precision and treatment strategies, though standardized protocols are needed.