For this purpose, recommendations have been formulated based on recent literature and expert opinion regarding the rationale, indications and contraindications for these procedures, as well as the radioiodine activities and the administration and patient preparation techniques to be used. Recommendations also are provided on pre-RAIT history and examinations, patient counselling and precautions that should be associated with (131)I iodine ablation and treatment. Furthermore, potential side effects of radioiodine therapy and alternate or additional treatments to this modality are reviewed. Appendices furnish information on dosimetry and post-therapy scintigraphy.

The European procedural guidelines for radionuclide imaging of myocardial perfusion and viability are presented in 13 sections covering patient information, radiopharmaceuticals, injected activities and dosimetry, stress tests, imaging protocols and acquisition, quality control and reconstruction methods, gated studies and attenuation-scatter compensation, data analysis, reports and image display, and positron emission tomography. If the specific recommendations given could not be based on evidence from original, scientific studies, we tried to express this state-of-art. The guidelines are designed to assist in the practice of performing, interpreting and reporting myocardial perfusion SPET. The guidelines do not discuss clinical indications, benefits or drawbacks of radionuclide myocardial imaging compared to non-nuclear techniques, nor do they cover cost benefit or cost effectiveness.

On the basis of the high and consistent expression of prostatespecific membrane antigen (PSMA) in metastatic prostate cancer (PC), the goal of this study was the development, preclinical evaluation, and first proof-of-concept investigation of a PSMA inhibitor for imaging and therapy (PSMA I&T) for 68 Ga-based PET and 177 Lu-based endoradiotherapeutic treatment in patients with metastatic and castration-resistant disease. Methods: PSMA I&T was synthesized in a combined solid phase and solution chemistry strategy. The PSMA affinity of nat Ga-/ nat Lu-PSMA I&T was determined in a competitive binding assay using LNCaP cells. Internalization kinetics of 68 Ga-and 177 Lu-PSMA I&T were investigated using the same cell line, and biodistribution studies were performed in LNCaP tumor-bearing CD-1 nu/nu mice. Initial human PET imaging studies using 68 Ga-PSMA I&T, as well as endoradiotherapeutic treatment of 2 patients with metastatic PC using 177 Lu-PSMA I&T, were performed. Results: PSMA I&T and its cold gallium and lutetium analog revealed nanomolar affinity toward PSMA. The DOTAGA (1,4,7,10-tetraazacyclododecane-1-(glutamic acid)-4,7,10-triacetic acid) conjugate PSMA I&T allowed fast and high-yield labeling with 68 Ga III and 177 Lu III . Uptake of 68 Ga-/ 177 Lu-PSMA I&T in LNCaP tumor cells is highly efficient and PSMA-specific, as demonstrated by competition studies both in vitro and in vivo. Tumor targeting and tracer kinetics in vivo were fast, with the highest uptake in tumor xenografts and kidneys (both PSMA-specific). First-in-human 68 Ga-PSMA I&T PET imaging allowed high-contrast detection of bone lesions, lymph node, and liver metastases. Endoradiotherapy with 177 Lu-PSMA I&T in 2 patients was found to be effective and safe with no detectable side effects. Conclusion: 68 Ga-PSMA I&T shows potential for high-contrast PET imaging of metastatic PC, whereas its 177 Lu-labeled counterpart exhibits suitable targeting and retention characteristics for successful endoradiotherapeutic treatment. Prospective studies on larger cohorts of patients are warranted and planned.

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This study demonstrates comparable remnant ablation rates in patients prepared for 131I remnant ablation with 3.7 GBq by either administering rhTSH or withholding thyroid hormone. rhTSH-prepared patients maintained a higher quality of life and received less radiation exposure to the blood.

The purpose of the present guidelines on the (131)I therapy of benign thyroid disorders formulated by the European Association of Nuclear Medicine (EANM) Therapy Committee is to provide advice to nuclear medicine clinicians on how to treat benign thyroid conditions employing optimal (131)I activities. The recommendations were formulated based on recent literature and expert opinion regarding rationale, indications and contraindications for the use of (131)I procedures, as well as the adequate (131)I activities in different thyroid disorders, and the administration and patient preparation techniques to be used. Recommendations are also provided on history and examinations before (131)I therapy, patient counselling and precautions associated with (131)I therapy. Furthermore, potential side effects and alternative treatment modalities are reviewed. Special attention is paid to these aspects in the treatment of children undergoing this procedure.

Chemokine ligand-receptor interactions play a pivotal role in cell attraction and cellular trafficking, both in normal tissue homeostasis and in disease. In cancer, chemokine receptor-4 (CXCR4) expression is an adverse prognostic factor. Early clinical studies suggest that targeting CXCR4 with suitable high-affinity antagonists might be a novel means for therapy. In addition to the preclinical evaluation of [68Ga]Pentixafor in mice bearing human lymphoma xenografts as an exemplary CXCR4-expressing tumor entity, we report on the first clinical applications of [68Ga]Pentixafor-Positron Emission Tomography as a powerful method for CXCR4 imaging in cancer patients. [68Ga]Pentixafor binds with high affinity and selectivity to human CXCR4 and exhibits a favorable dosimetry. [68Ga]Pentixafor-PET provides images with excellent specificity and contrast. This non-invasive imaging technology for quantitative assessment of CXCR4 expression allows to further elucidate the role of CXCR4/CXCL12 ligand interaction in the pathogenesis and treatment of cancer, cardiovascular diseases and autoimmune and inflammatory disorders.

Dosimetry of organs and tumors helps to assess risks and benefit of treatment with Lu-DOTATATE/DOTATOC. However, it is often not performed in clinical routine because of additional efforts, the complexity of data collection and analysis, and the additional burden for the patients. Aiming at a simplification of dosimetry, we analyzed the accuracy of a theoretically substantiated approximation, which allows the calculation of absorbed doses from a single measurement of the abdominal activity distribution. Activity kinetics were retrospectively assessed from planar images in 29 patients with neuroendocrine tumors (NETs; = 21) or meningioma ( = 8) after the administration of Lu-DOTATATE ( = 22) or Lu-DOTATOC ( = 7). Mono- or biexponential functions were fitted to measured data in 54 kidneys, 25 livers, 27 spleens, and 30 NET lesions. It was evaluated for each fit function how well the integral over time was represented by an approximation calculated as the product of the time t of a single measurement, the expected reading at time t, and the factor 2/ln(2). Tissue-specific deviations of the approximation from the time integral were calculated for time points t of 24, 48, 72, 96, 120, and 144 h. The correlation between time integral and approximation improved with increasing time t Pearson r exceeded 0.95 for a t of 96 h or more in all tissues. The lowest maximum errors were observed at a t of 96 h, with deviations of the approximation from the time integral of median +5% (range, -9% to +17%) for kidneys, +6% (range, -7% to +12%) for livers, +8% (range, +2% to +20%) for spleens, and +6% (range, -11% to +16%) for NET lesions. Accuracy was reduced for measurements after 72 or 120 h. For measurements after 24, 48, and 144 h, the approximation led to large deviations for some of the patients, in particular unacceptable underestimates of the absorbed dose to the kidneys. A single quantitative measurement of the abdominal activity concentration by SPECT/CT 4 d after the administration ofLu-DOTATATE/DOTATOC provides a 3-dimensional dose map and can be used to estimate the doses actually absorbed in the treatment cycle with minor additional resources and effort.