Dynamic total-body PET/CT imaging with reduced acquisition time shows acceptable performance in quantification of [18F]FDG tumor kinetic metrics

• Published in: European journal of nuclear medicine and molecular imaging Vol. 51; no. 5; pp. 1371 - 1382
• Main Authors: Liu, Guobing, Shi, Yimeng, Hou, Xiaoguang, Yu, Haojun, Hu, Yan, Zhang, Yiqiu, Shi, Hongcheng
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2024; Springer Nature B.V
• Subjects: Cardiology; Computed tomography; Fluorine isotopes; Glucose; Imaging; Medical imaging; Medicine; Medicine & Public Health; Nuclear Medicine; Oncology; Original Article; Orthopedics; Positron emission; Positron emission tomography; Radiology; Tumors; Short-time imaging; F]-fluoro-2-deoxy-D-glucose; Total-body positron emission tomography; 2-; Dynamic imaging; F]FDG; 2-[18F]-fluoro-2-deoxy-D-glucose ([18F]FDG)
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-023-06526-4

Purpose To investigate the feasibility of reducing the acquisition time for continuous dynamic positron emission tomography (PET) while retaining acceptable performance in quantifying kinetic metrics of 2-[ 18 F]-fluoro-2-deoxy-D-glucose ([ 18 F]FDG) in tumors. Methods In total, 78 oncological patients underwent total-body dynamic PET imaging for ≥ 60 min, with 8, 20, and 50 patients receiving full activity (3.7 MBq/kg), half activity (1.85 MBq/kg), and ultra-low activity (0.37 MBq/kg) of [ 18 F]FDG, respectively. The dynamic data were divided into 21-, 30-, 45- and ≥ 60-min groups. The kinetic analysis involved model fitting to derive constant rates ( V B , K 1 to k 3 , and Ki ) for both tumors and normal tissues, using both reversible and irreversible two-tissue-compartment models. One-way ANOVA with repeated measures or the Freidman test compared the kinetic metrics among groups, while the Deming regression assessed the correlation of kinetic metrics among groups. Results All kinetic metrics in the 30-min and 45-min groups were statistically comparable to those in the ≥ 60-min group. The relative differences between the 30-min and ≥ 60-min groups ranged from 12.3% ± 15.1% for K 1 to 29.8% ± 30.0% for V B , and those between the 45-min and ≥ 60-min groups ranged from 7.5% ± 8.7% for Ki to 24.0% ± 24.3% for V B . However, this comparability was not observed between the 21-min and ≥ 60-min groups. The significance trend of these comparisons remained consistent across different models (reversible or irreversible), administrated activity levels, and partial volume corrections for lesions. Significant correlations in tumor kinetic metrics were identified between the 30-/45-min and ≥ 60-min groups, with Deming regression slopes > 0.813. In addition, the comparability of kinetic metrics between the 30-min and ≥ 60-min groups were established for normal tissues. Conclusion The acquisition time for dynamic PET imaging can be reduced to 30 min without compromising the ability to reveal tumor kinetic metrics of [ 18 F]FDG, using the total-body PET/CT system.