Whole-body parametric PET imaging will replace conventional image-derived PET metrics in clinical oncology

Current clinical whole-body PET imaging protocols reflect the trend followed in conventional nuclear medicine in that they are optimized to produce the best image quality for qualitative visual interpretation instead of quantitative assessment of biological parameters. Multi-bed acquisitions are commonly performed to produce a static PET image depicting the three-dimensional spatial distribution of the tracer uptake over the acquisition time frame. Conventional semi-quantitative image-derived PET metrics, such as the Standardized Uptake Value (SUV), are then used in the context of clinical oncology. Methodological developments reported in recent literature seem to indicate reasonable evidence that clinically adoptable dynamic whole-body imaging protocols enable quantitative parametric imaging (map representing clinically relevant set of physiological parameters at the voxel level), especially when combined with direct 4D reconstruction to achieve better noise properties. These advances stimulated the integration of these developments in the form of a commercial package (FlowMotion MultiParametric PET) supplied to end users by Siemens Healthineers. While some think that parametric whole-body imaging is the future and will be integrated in clinical protocols to support conventional SUV imaging in clinical oncology studies, others keep on watching arguing that the pilot results reported in the literature are still embryonic and that the clinical relevance of the technique still remains to be demonstrated. This is the topic addressed in this month's Point/Counterpoint debate. This article is protected by copyright. All rights reserved.