Abstract:
ObjectiveTo investigate the differences in 18F-FDG uptake on different edge sign areas of malignant solitary pulmonary nodules and to analyze the effects of tumor biological growth pattern on radioactivity distribution of 18F-FDG.
MethodsRetrospective analysis of the data on 18F-FDG PET/CT images from 50 collected cases with malignant solitary pulmonary nodules was conducted to determine 18F-FDG uptake value, which is expressed as average standardized uptake value (SUVave), maximum standardized uptake value (SUVmax), and ΔSUV (SUVmax-SUVave), at the region of interest to investigate the differences in radioactive 18F-FDG uptake on the positive edge sign areas of the nodules. Comparison of mean in multiple groups was conducted with LSD method.
ResultsIn 50 patients with malignant solitary pulmonary nodules, spicule signs occurred in 35 cases (SUVave=4.99±2.98; SUVmax=5.87±3.48; ΔSUV=0.88±0.67); lobulation signs appeared in 41 cases (SUVave=6.95±3.30; SUVmax=8.43±3.98; ΔSUV=1.48±1.04); pleural retraction signs developed in 26 cases (SUVave=4.45±2.03; SUVmax=5.40±2.45; ΔSUV=0.95±0.82); vessel convergence signs materialized in 30 cases (SUVave=6.36±3.94; SUVmax=7.78±5.22; ΔSUV=1.42±1.52). Compared with the spicule (LSD, P=0.008, 0.006, 0.015), and pleural retraction sign groups (LSD, P=0.002, 0.003, 0.049), SUVave, SUVmax, and ΔSUV of the lobulation sign group were much higher. Compared with the pleural retraction sign group, SUVave and SUVmax of the vessel convergence sign group were much higher (LSD, P=0.026, 0.026).
ConclusionsSignificant differences were observed in the distributions of radioactive 18F-FDG uptake between predominant proliferative and infiltrative areas. Thus, 18F-FDG PET/CT imaging can virtually reflect the heterogeneous distribution of proliferative and invasive areas in different tumor regions.