Whole-Body Distribution and Radiation Dosimetry of 68 Ga-NOTA-RGD, a Positron Emission Tomography Agent for Angiogenesis Imaging Joong Hyun Kim, 1–3 Jae Sung Lee, 1–5 Keon Wook Kang, 1,3,6 Ho-Young Lee, 1 Sae-Won Han, 7 Tae-You Kim, 7,8 Yun-Sang Lee, 1,3 Jae Min Jeong, 1–3 and Dong Soo Lee 1–3,8 Abstract 68 Ga 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 68 Ga-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 68 Ga-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 gall- bladder, 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 68 Ga-NOTA-RGD was highest in the kidneys and urinary bladder. Radiation doses to kidneys and urinary bladder were 71.6 – 28.4 lGy/MBq and 239.6 – 56.6 lGy/MBq. Mean effective doses were 25.0 – 4.4 lSv/MBq using International Commission of Radiation Protection (ICRP) publication 60 and 22.4 – 3.8 lSv/MBq using ICRP publication 103 weighting factor. We evaluated the radiation dosimetry of 68 Ga labeled NOTA-RGD, which has an acceptable effective radiation dose. Key words: angiogenesis, biodistribution, dosimetry, PET, RGD Introduction A ngiogenesis is the physiological process involving the growth of new blood vessels, and an essential develop- mental process. It is regulated by the interplay of growth factors and inhibitors, and their imbalances can lead to dis- ease. Therefore, the regulation of angiogenesis offers a strat- egy for the treatment of cancer and other disorders, and intensive efforts have been undertaken to develop such ther- apeutic strategies. 1–3 The integrins are a family of cell-surface receptors that bind extracellular matrix components, organize the cytoskeleton, and activate intracellular signaling pathways. 4 Integrin a v b 3 is a member of this family of receptors, highly expressed on activated endothelial cells during angiogenesis, and associated with the tumor growth, invasion, and metastasis. 5–7 1 Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Korea. 2 Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul, Korea. 3 Institute of Radiation Medicine, Medical Research Center, Seoul National University College of Medicine, Seoul, Korea. Departments of 4 WCU Brain and Cognitive Sciences and 5 Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea. 6 Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea. 7 Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. 8 WCU Molecular Medicine & Biopharmaceutical Science, Seoul National University College of Medicine, Seoul, Korea. Address correspondence to: Jae Sung Lee; Department of Nuclear Medicine, Seoul National University College of Medicine; 28 Yungun-Dong, Chongno-Gu, Seoul 110-744, Korea E-mail: jaes@snu.ac.kr Keon Wook Kang; Department of Nuclear Medicine, Seoul National University College of Medicine, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Korea E-mail: kangkw@snu.ac.kr CANCER BIOTHERAPY AND RADIOPHARMACEUTICALS Volume 27, Number 1, 2012 ª Mary Ann Liebert, Inc. DOI: 10.1089/cbr.2011.1061 65