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Radionuclide-based Diagnosis and Therapy of Prostate Cancer
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Sven-Erik Strand, Mohamed Altai, Joanna Strand, David Ulmert
Iodine-131 is mostly produced by neutron-irradiation of a natural tellurium target in nuclear reactors and decays emitting both β- particles and γ rays with a half-life of 8.02 days. The co-emitted high energy gamma (364 keV; 81.7%) also permits imaging. NaI (sodium/iodide) symporter-expressing tissues – for example, thyroid, stomach and salivary glands – are known to sequester 131I (and other radioiodine isotopes), thus do not require the coupling of the radioisotope to a targeting vector. For thyroid studies, iodine isotopes are prepared as sodium salt, Na131I, and administered orally or injected. However, lack of targeting may result in the accumulation of the radioactive isotope in non-diseased tissues such as the stomach and salivary gland.
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Iodine, I, is a nonmetallic element of the halogen family. There is only one natural stable isotope: iodine 127. There are many artificial radioactive isotopes. Iodine is a heavy, grayish-black solid or granules having a metallic luster and characteristic odor. It is readily sublimed to a violet vapor and insoluble in water. Iodine is toxic by ingestion and inhalation and is a strong irritant to the eyes and skin, with a TLV ceiling of 0.1 ppm in air. Iodine 131 is a radioactive isotope of iodine and has a half-life of 8 days. It is used in the treatment of goiter, hyperthyroidism and other disorders. It is also used as an internal radiation therapy source. Most iodine compounds are not radioactive.
Radiation Therapy and Radiation Safety in Medicine
Published in Suzanne Amador Kane, Boris A. Gelman, Introduction to Physics in Modern Medicine, 2020
Suzanne Amador Kane, Boris A. Gelman
Examples of radionuclides used in unsealed source therapy are iodine-131, with a half-life of 8.0 days and a beta range of 3 mm, and phosphorus-32, with a half-life of 14.3 days and a beta range of 10 mm. Because iodine is effectively partitioned into the thyroid gland and cleared from the rest of the body, iodine-131 administered orally is used for the treatment of thyroid cancer and hyperthyroidism (overactive thyroid gland). In the case of iodine-131, its emission of gamma rays allows gamma camera or SPECT imaging to be used to follow the course of treatment. Phosphorus-32 has a pronounced effect on blood-forming tissues, so it can be used in the treatment of leukemia and other blood disorders.
Theranostic approaches in nuclear medicine: current status and future prospects
Published in Expert Review of Medical Devices, 2020
Luca Filippi, Agostino Chiaravalloti, Orazio Schillaci, Roberto Cianni, Oreste Bagni
Although theranostics is involving a growing number of scientific disciplines, especially in the field of nanotechnology [3], this innovative medical approach is deeply connected with nuclear medicine. Radionuclide imaging, in fact, offers the unique opportunity to detect and quantify the expression of a specific tumor biomarker through the use of a certain radiopharmaceutical labeled with isotopes emitting radiations suitable for imaging and, subsequently, the same radiopharmaceutical can be labeled with a radionuclide emitting alpha or beta particles to obtain a tumoricidal effect [4]. In this scenario, the radioactive iodine (131I) perhaps represents the oldest application of theranostics, since post thyroidectomy ablation of residual differentiated thyroid cancer (DTC) is based on the fact that thyroid follicular cells can incorporate 131I, which is both a gamma (i.e. diagnostics) and beta emitter (i.e. therapy) [5]. Thus, the same element can be used for the detection of iodine-avid residual thyroid tissue and for therapeutic purposes.
Overview of biological mechanisms of human carcinogens
Published in Journal of Toxicology and Environmental Health, Part B, 2019
Nicholas Birkett, Mustafa Al-Zoughool, Michael Bird, Robert A. Baan, Jan Zielinski, Daniel Krewski
Radionuclides emitting β-particles were reviewed separately when adequate data were available, and evaluated as follows. There is sufficient evidence in humans for the carcinogenicity of exposures during childhood and adolescence to short-lived radioisotopes of iodine, including iodine-131. These exposures produce cancer of the thyroid. Similarly, there is sufficient evidence in humans for the carcinogenicity of therapeutic administration of phosphorus-32, as phosphate, which induces acute leukemia in patients with polycythemia vera. In addition, there is sufficient evidence in humans for the carcinogenicity of external and internal exposures to fission products, including strontium-90, which initiates solid cancers and leukemia. This Group-1 classification was considered to be applicable to all β-particle-emitting radionuclides, based predominantly upon the following considerations: (1) all radionuclides that emit β-particles and that have been adequately studied, were noted to induce cancer in humans and experimental animals and (2) β-particles emitted by radionuclides, irrespective of their source, produce similar patterns of secondary ionizations and the same type of localized damage to biological molecules including to DNA. These effects include DNA double-strand breaks, chromosomal aberrations in circulating lymphocytes and gene mutations in humans in vivo, and cell transformation.
Nuclear Medicine in Oncology
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2018
Carla Oliveira, Rui Parafita, Ana Canudo, Joana Correia Castanheira, Durval C. Costa
According to Chen and Wong (Chen & Wong 2014), cancer THERANOSTICS is a concept by which cancer diagnosis and cancer therapy are combined with the specific aim of achieving early diagnosis, more accurate molecular imaging diagnostic targets and precise treatment at the right timing and proper dose, followed by real time monitoring of treatment efficacy, most frequently with specific molecular targets. It is therefore understood that radiopharmaceuticals are at the very forefront of THERANOSTICS, since changing the radionuclide one can use the same molecular target for diagnostic imaging (for instance 68Ga-DOTATATE) and for therapeutic procedures (177Lu-DOTATATE). In Nuclear Medicine, this concept has been used for decades via IODINE-131 for diagnosis and therapy of thyroid nodules in hyperthyroidism and for metastatic differentiated thyroid carcinoma.