Page 34 - 89Zr-Immuno-PET:Towards a Clinical Tool to Guide Antibody-based Therapy in Cancer

Chapter 2
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Patient weight (kg)
Figure 3. Difference between PET assessed blood pool activity and sampled blood activity of 89Zr-cmAb U36 as function of patient weight. Difference in activity was assessed at 1 h (∆), 24 h (○), 72 h (■), and 144 h (♦) after injection.
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Time after injection (h)
Figure 4. Mean 89Zr-cmAb U36 activity in blood (Bq/cm3) of the study population: PET assessed bloodpool activity within the left ventricle of the heart (■), and sampled bloodpool activity (▲).
Quantification of mAb uptake in tumors
Antibody uptake was assessed on 144 h p.i. scans for all primary tumors, and compared with uptake data from biopsies obtained 168 h p.i. Comparison of %ID/g derived from biopsy data and PET data, respectively, showed a good agreement with slightly lower values for PET (mean deviation -8.4 ± 34.5%). The mean tumor uptake at 168 h p.i. as assessed by biopsies appeared to be 0.019 ± 0.010 %ID/g (range 0.006 - 0.038 %ID/g).
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Activity (Bq/cm3)
Difference (%)
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