PET-based biodistribution and radiation dosimetry of epidermal growth factor receptor-selective tracer 11C-PD153035 in humans

Abstract

The present study estimated the biodistribution and radiation-absorbed dose of epidermal growth factor receptor (EGFR) radioligand 11C-PD153035 in whole-body PET examinations of healthy volunteers. Methods: Two-dimensional whole-body PET was performed on 9 subjects after injection of 11C-PD153035 at 329.3 ± 77.8 MBq (mean ± SD). A total of 12 frames were acquired for approximately 90 min in 7 segments of the body. Regions of interest were drawn on PET images of source organs. Residence time was calculated as the area under the time-activity curve. Radiation dosimetry was calculated from organ residence time by use of MIRDOSE3 software. Results: The renal and hepatobiliary systems played important roles in 11C-PD153035 excretion from the body, accounting for the excretion of approximately 23% and 19% of the injected radioactivity, respectively. Blood-pool activity was only moderate and declined over time. Tracer accumulation in the lungs, bone marrow, and muscles was slight, resulting in low background activity in the chest. The organs with the highest radiation-absorbed doses were the urinary bladder and the gallbladder; the effective doses were 6.08E-02 ± 1.85E-02 and 2.40E-02 ± 8.01E-03 mGy/MBq, respectively. The effective dose equivalent was 7.43E-03 ± 1.10E-03 mSv/MBq, and the dose-limiting organ was the urinary bladder. Conclusion: On the basis of the estimated absorbed dose, 11C-PD153035 displayed a favorable radiation dose profile in humans and therefore could be used in multiple PET examinations of the same subject per year. 11C-PD153035 is a promising ligand for the investigation of EGFR in humans, especially in chest tumors such as non-small cell lung cancer. Copyright © 2009 by the Society of Nuclear Medicine, Inc.