SUVpeak Performance in Lung Cancer: Comparison to Average SUV from the 40 Hottest Voxels

The performance of an average SUV over a 1-mL-volume sphere within an F-18-FDG-positive lesion resulting in the highest possible value (SUVpeakW) was compared with that of an average SUV computed from the 40 hottest voxels, irrespective of their location within the lesion (SUVmax-40). Methods: Dynamic PET performed in 20 lung cancer lesions yielded for each SUV metric its mean value, relative measurement error, and repeatability (MEr-R). Results: SUVpeakW mean value was significantly 9.66% lower than that of SUVmax-40 (P < 0.0001). SUVpeakW and SUVmax-40 MEr-R were significantly lower than the MEr-R of SUVmax (the hottest voxel): 9.35%-13.21% and 8.84%-12.49% versus 13.86%-19.59%, respectively, (95% confidence limit; P < 0.0001). Although being marginal, SUVpeakW MEr-R was not significantly greater than SUN/(max-40) MEr-R (P = 0.086). Conclusion: SUVmax-40 is more likely to represent the most metabolically active portions of tumors than SUVpeakW, with close variability performance.