Figure 3
Increased FDG uptake rates in lymphoid tissues of C.IL6Myc mice undergoing PCT development. (a) Elevated metabolic activity in three different stages of tumor progression. Included in the analysis were CLN, ALN, (ILN and MLN as well as SPL. Ages of mice, which correspond to early (white), mid (hatched) and late (black) stages of tumor progression, are indicated at the top left. The number of tissue samples is indicated at the bottom. Regions of interest defined on PET images were placed in areas of focal FDG uptake not explained by the physiologic distribution and excretion of FDG. In cases where the identification of the underlying tissue was not straightforward, these regions were put in anatomical context using fused PET/CT images. Metabolic tissue volumes, Volmetab (top) and maximal standardized uptake values, SUVmax (bottom), were calculated and mean values were compared using the two-tailed Mann–Whitney test. Significant differences between stages of tumor progression (two-tailed Mann–Whitney test) are indicated as *P<0.05, **P<0.01 and ***P<0.001. (b) FDG uptake in MLN is correlated with age of mouse. Volmetab (top) and SUVmax (bottom) were obtained from 34 PET scans of all Tg mice included in Figure 3 (n=11). Correlation parameters including linear regression coefficients (r2) and significance values (P) are indicated. Supplementary Figure 2 presents SUVmean and TLG data on MLN and Supplementary Figure 3 shows complete results (volume, SUVmax, SUVmean, TLG) on all other lymphoid tissues included here (CLN, ALN, ILN and SPL).
