Strontium-89

Strontium-89 (Template:SimpleNuclide) is a radioactive isotope of strontium with a half-life of 50.56 days.<ref name="nubase" /> It undergoes β⁻ decay (with practically no gamma rays) into yttrium-89.<ref name="nndc" /> Strontium-89 has application in medicine. It is also a fission product, but is produced technically by neutron capture on ordinary strontium.<ref>[1]</ref>

History

Strontium-89 was first synthesized in 1937 by D. W. Stewart et al. at the University of Michigan; it was synthesized via irradiation of stable strontium (the ⁸⁸Sr isotope) with deuterons.<ref name=discovery>Template:Cite journal</ref> Biological properties and applications of strontium-89 were studied for the first time by Belgian scientist Charles Pecher.<ref>Template:Cite journal</ref><ref name=":2">Template:Cite book</ref> Pecher filed a patent in May 1941 for the synthesis of strontium-89 and yttrium-86 using cyclotrons, and described the therapeutic use of strontium.<ref>Template:Cite patent</ref>

Physiological effects and medical use

File:Metastron (Strontium-89), GE Healthcare.jpg

Metastron, a preparation of strontium-89 chloride made by GE Healthcare and used for purposes such as prostate cancer treatment.<ref name="Strontium 89 (Metastron) treatment">Template:Cite web</ref>

Strontium belongs to the same periodic family as calcium (alkaline earth metals), and is metabolised in a similar fashion, preferentially targeting metabolically active regions of the bone. ⁸⁹Sr is an artificial radioisotope used in the treatment of osseous (bony) metastases of bone cancer.<ref name="HalperinPerez2008">Template:Cite book</ref><ref name="BaumanCharette2005">Template:Cite journal</ref>

In circumstances where cancer patients have widespread and painful bony metastases, the administration of ⁸⁹Sr results in the delivery of beta particles directly to the area of bony problem, where calcium turnover is greatest.<ref name="MertensFilipczak1998">Template:Cite journal</ref> Consequently, intravenous or intracavity administration of ⁸⁹Sr may be helpful in the palliation of painful bony metastases, as it allows radiation to be targeted at metastatic lesions, inducing apoptosis of cells, membrane and protein damage. Subsequently, bone pain resulting from cytokine release at the site of lesions, bone-associated nerve compression and stretching of the periosteum may be reduced. Treatment with ⁸⁹Sr has been particularly effective in patients with hormonally-resistant prostate cancer, often leading to a decreased requirement for opioid analgesics, an increase in time until further radiation is needed, and a decrease in tumour markers.

See also

• Isotopes of strontium
• Alpharadin, radium-223 with similar clinical use