Whole-Body Distribution and Radiation Dosimetry of 68Ga-NOTA-RGD, a Positron Emission Tomography Agent for Angiogenesis Imaging

Ga-68 labeled NOTA-RGD was a recently developed positron emission tomography (PET) radiotracer for the visualization of angiogenesis, and is regarded as a promising imaging agent for cancer and several other disorders. In this study, we investigated the whole-body distribution and radiation dosimetry of Ga-68-NOTA-RGD in humans. Ten cancer patients (53.7+/-13.5 years; 61.5+/-7.4 kg) participated in this study. PET scans were performed using a PET/computed tomography (scanner in three-dimensional mode). After an intravenous injection of 172.4+/-20.5 MBq of Ga-68-NOTA-RGD, eight serial whole-body scans were performed during 90 minutes. Volumes of interest were drawn manually over the entire volumes of the urinary bladder, the gallbladder, heart, kidneys, liver, lungs, pancreas, spleen, and stomach. Time-activity curves were obtained from serial PET scan data. Residence times were calculated from areas under curve of time-activity curves and used as input to the OLINDA/EXM 1.1 software. The uptake of Ga-68-NOTA-RGD was highest in the kidneys and urinary bladder. Radiation doses to kidneys and urinary bladder were 71.6+/-28.4 mu Gy/MBq and 239.6+/-56.6 mu Gy/MBq. Mean effective doses were 25.0+/-4.4 mu Sv/MBq using International Commission of Radiation Protection (ICRP) publication 60 and 22.4+/-3.8 mu Sv/MBq using ICRP publication 103 weighting factor. We evaluated the radiation dosimetry of Ga-68 labeled NOTA-RGD, which has an acceptable effective radiation dose.