Whole-Body Distribution and Radiation Dosimetry of⁶⁸Ga-NOTA-RGD, a Positron Emission Tomography Agent for Angiogenesis Imaging

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 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 (68)Ga-NOTA-RGD was highest in the kidneys and urinary bladder. Radiation doses to kidneys and urinary bladder were 71.6 ± 28.4 μ Gy/MBq and 239.6 ± 56.6 μ Gy/MBq. Mean effective doses were 25.0 ± 4.4 μ Sv/MBq using International Commission of Radiation Protection (ICRP) publication 60 and 22.4 ± 3.8 μ Sv/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.

Plasma Pharmacokinetics, Whole-Body Distribution, Metabolism, and Radiation Dosimetry of 68Ga Bombesin Antagonist BAY 86-7548 in Healthy Men

“…Although 68 Ga has been used extensively for the labeling of synthetic peptides, human dosimetry data are available only from peptide analogs that bind to somatostatin receptors or a v b 3 integrin. The effective dose of BAY 86-7548 reported here (0.051 mSv/MBq) is comparable but slightly higher than those of 68 Ga-DOTATOC (0.023 mSv/MBq), 68 Ga-DOTANOC (0.025 mSv/MBq), and 68 Ga-NOTA-RGD (0.022 mSv/ MBq) (16)(17)(18). The effective dose of 18 F-FDG is 0.019 mSv/MBq according to the International Commission on Radiological Protection, publication 106 (19).…”

“…PET/CT plays an important role in the attempt to improve and individualize therapeutic approaches in oncology. The most widely used tracer, 18 F-FDG, shows a high excretion in the urinary bladder and demonstrates generally an unsatisfactory uptake in PCa, especially in the early phase (4,5). Tracers that depict lipid metabolism such as 11 C-choline and 11 C-acetate have already been applied for imaging PCa, but they accumulate also in prostatic hyperplasia, with overlapping uptake in benign and malignant intraprostatic lesions (6)(7)(8).…”

“…Preclinical data suggest the possibility of a high PCa-specific signal with radiolabeled bombesin analogs targeting GRPr (10). These analogs could potentially provide better and more specific diagnosis than 18 F-FDG or tracers such as 11 C-choline or 11 C-acetate. 68 Ga-DOTA-4-amino-1-carboxymethylpiperidine-D-PheGln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 (BAY 86-7548; also known as RM2) is a bombesin antagonist with high GRPr affinity.…”

In Vivo Evaluation of Angiogenic Activity and Its Correlation with Efficacy of Indirect Revascularization Surgery in Pediatric Moyamoya Disease

“…Accordingly, P Bas and P Str were slightly higher on long-term follow-up SPECT than on immediate postoperative SPECT. The actual time course of angiogenic activity can be assessed by serial follow-up study using noninvasive 68 Ga-RGD PET, and such repetitive evaluation of angiogenic activity would be available within a tolerable range of radiation exposure (25). One of the intriguing results of our study is that postoperative angiogenic activity was inversely correlated with perfusion improvement.…”

Role of Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Imaging in Diagnosis and Staging of Lung Cancer

“…Tümör anjiogenezi ile ilişkili olarak aktifleşen endotel hücrelerinde integrin adı verilen moleküllerin ekspresyonu artar. İntegrinlerin görüntülenmesine yönelik F-18 ve Ga-68 ile işaretli çeşitli PET ajanları geliştirilmiş, bu ajanlar kullanılarak akciğer kanserinde anjiogenezin PET ile görüntülenmesine yönelik çalışmalar yapılmıştır (87,88,89). CXCR4 çeşitli solid kanseri türlerinde artmış ekspresyon gösteren, tümörün metastaz yapma potansiyeli ile ilişkili bir kemokin reseptörüdür (90,91).…”