What and how should we measure in paediatric oncology FDG-PET/CT? Comparison of commonly used SUV metrics for differentiation between paediatric tumours

• Published in: EJNMMI research 2019-12, Vol.9 (1), p.115-9, Article 115
• Main Authors: Blautzik, Janusch, Grelich, Leonie, Schramm, Nicolai, Henkel, Rebecca, Bartenstein, Peter, Pfluger, Thomas
• Format: Article
• Language: English
• Subjects: Cardiac Imaging; Children; Correlation analysis; Differentiation; FDG PET/CT; Imaging; Liver; Lymphoma; Mediastinum; Medicine; Medicine & Public Health; Nuclear Medicine; Oncology; Original Research; Orthopedics; Paediatric oncology; Radiology; Regression analysis; Sarcoma; Sport utility vehicles; SUV; Tumors
• ISSN: 2191-219X; 2191-219X
• DOI: 10.1186/s13550-019-0577-7

Background In clinical routine, SUV max and SUV peak are most often used to determine the glucose metabolism in tumours by 18 F-FDG PET/CT. Both metrics can be further normalised to SUVs in reference regions resulting in a SUV ratio (SUV ratio ). The aim of the study was to directly compare several widely used SUVs/SUV ratios with regard to differentiation between common tumours in paediatric patients; a special focus was put on characteristics of reference region SUVs. Methods The final study population consisted of 61 children and adolescents with diagnoses of non-Hodgkin lymphoma (NHL, n = 25), Hodgkin lymphoma (HL, n = 14), and sarcoma ( n = 22). SUV metrics included SUV max and SUV peak as well as both parameters normalised to liver and mediastinal blood pool, respectively, yielding the SUV ratios SUV max/liver , SUV max/mediastinum , SUV peak/liver , and SUV peak/mediastinum . Results The metrics SUV max , SUV peak , SUV max/liver , and SUV peak/liver all proved to be sensitive for tumour differentiation ( p ≤ 0.008); in contrast, SUV max/mediastinum and SUV peak/mediastinum revealed to be non-sensitive approaches. Correlation analyses showed inverse associations between reference region SUVs and SUV ratios ( p < 0.05). Multiple regression analyses demonstrated significant effects of factors as bodyweight and uptake time on reference region SUVs ( p < 0.01), and thus indirectly on the corresponding SUV ratios . Conclusions In the paediatric population, the ability to differentiate between common tumours remarkably varies between SUV metrics. When using SUV ratios , the choice of reference region is crucial. Factors potentially influencing reference region SUVs (and thus SUV ratios ) should be taken into account in order to avoid erroneous conclusions. When not possible, SUV max and SUV peak represent less complex, more robust alternatives.