TheraSphere® Yttrium 90 Glass Microspheres

The University of Cincinnati is reporting that its physicians are using “millions of glass beads” as a treatment for advanced hepatocellular carcinoma. The technology they are using is called TheraSphere® Yttrium 90 Glass Microspheres, designated as a “humanitarian device” (i.e. with no demonstrated effectiveness) by the FDA. The therapy is a product of MDS Nordion company.
Company explains:

TheraSphere® consists of insoluble glass microspheres where yttrium-90 is an integral constituent of the glass. The mean sphere diameter ranges from 20 to 30 µm. Each milligram contains between 22,000 and 73,000 microspheres…
Yttrium 90, a pure beta emitter, decays to stable zirconium 90 with a physical half-life of 64.2 hours (2.67 days). The average energy of the beta emissions from yttrium 90 is 0.9367 MeV.
Following embolization of the yttrium 90 glass microspheres in tumorous liver tissue, the beta radiation emitted provides a therapeutic effect. The microspheres are delivered into the liver tumor through a catheter placed into the hepatic artery that supplies blood to the tumor. The microspheres, being unable to pass through the vasculature of the liver due to arteriolar capillary blockade, are trapped in the tumor and exert a local radiotherapeutic effect with some concurrent damage to surrounding normal liver tissue.

To advance its therapy, the company has recently launched a clinical trial to “further… clinical experience and knowledge of this treatment.”
Clinical trial press release…
Product page…
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