Availability of Yttrium-90 from Strontium-90: A Nuclear Medicine Perspective

Yttrium-90 (T½ 64.1 hours, Eβmax=2.28 MeV) is a pure β− particle emitting radionuclide with well-established applications in targeted therapy. There are several advantages of 90Y as a therapeutic radionuclide. It has a suitable physical half-life (∼64 hours) and decays to a stable daughter product 90Zr by emission of high-energy β− particles. Yttrium has a relatively simple chemistry and its suitability for forming complexes with a variety of chelating agents is well established. The 90Sr/90Y generator is an ideal source for the long-term continuous availability of no-carrier-added 90Y suitable for the preparation of radiopharmaceuticals for radionuclide therapy. The parent radionuclide 90Sr, which is a long-lived fission product, is available in large quantities from spent fuel. Several useful technologies have been developed for the preparation of 90Sr/90Y generators. There are several well-established radiopharmaceuticals based on monoclonal antibodies, peptides, and particulates labeled with 90Y, that are in regular use for the treatment of some forms of primary cancers and arthritis. At present, there are no generators for the elution of 90Y that can be set up in a hospital radiopharmacy. The radionuclide is procured from manufacturers and the radiopharmaceuticals are formulated on site. This article reviews the development of 90Sr/90Y generator and the development of 90Y radiopharmaceuticals.