Diagnosis
Disease activity and vascular involvement in retroperitoneal fibrosis: first experience with fully integrated 18F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging compared to clinical and laboratory parameters
K. Thuermel1, I. Einspieler2, S. Wolfram3, P. Moog4, R. Meier5, M. Schwaiger6, U. Heemann7
- Department of Nephrology and Rheumatology, Klinikum rechts der Isar, Technical University of Munich, Germany. klaus.thuermel@mri.tum.de
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Germany.
- Department of Nephrology and Rheumatology, Klinikum rechts der Isar, Technical University of Munich, Germany.
- Department of Nephrology and Rheumatology, Klinikum rechts der Isar, Technical University of Munich, Germany.
- Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, Germany.
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Germany.
- Department of Nephrology and Rheumatology, Klinikum rechts der Isar, Technical University of Munich, Germany.
CER9338
2017 Vol.35, N°1 ,Suppl.103
PI 0146, PF 0154
Diagnosis
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PMID: 27974103 [PubMed]
Received: 13/02/2016
Accepted : 01/07/2016
In Press: 14/12/2016
Published: 20/04/2017
Abstract
OBJECTIVES:
The aim of this study was to evaluate the value of fully integrated [18F]-FDG PET/MRI in the assessment of retroperitoneal fibrosis with regard to disease activity, extent and vascular involvement compared to clinical and laboratory parameters.
METHODS:
Seventeen [18F]-FDG PET/MRI examinations were performed in fourteen patients. Qualitative (visual 4-point scale) and quantitative PET parameters (maximum standardised uptake value, SUVmax; target-background ratio, TBR) as well as RF thickness and volume were correlated to clinical and inflammatory parameters and compared between therapy-naïve patients and patients under immunosuppression. Evidence for associated large-vessel vasculitis was examined. Magnetic resonance angiography (MRA) was performed to detect aneurysms or stenoses. Results. Clinical parameters, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) only incompletely displayed inflammatory activity and did not correlate with PET/MRI parameters. In 29% (4/17) resp. 50% (8/16) of PET/MRI examinations active disease was detected although CRP resp. ESR were in the normal range. SUVmax, TBR and volume of the retroperitoneal mass differed significantly between therapy-naïve patients and patients under therapy (SUVmax p=0.004, TBR p=0.015, volume p=0.015), whereas thickness of the retroperitoneal mass did not (p=0.406). Large-vessel vasculitis was detected in 21% (3/14) and aortic aneurysms in 14% (2/14) of patients. Vasculitis occurred apart from the site of RF in two patients.
CONCLUSIONS:
Whole body hybrid [18F]-FDG-PET/MRI is superior to clinical and inflammatory parameters in disease activity assessment of RF. There may be substantial disease activity despite inflammatory parameters in the normal range. Associated large-vessel vasculitis and aneurysms may occur apart from the site of RF.
