SIR-Spheres® Y-90 resin microspheres are a medical device used in selective internal radiation therapy (SIRT).

- The microspheres are extremely small resin beads, approximately 32 microns in diameter, about a third of the width of a human hair.
- They have a density similar to that of blood cells which allows them to travel easily within the bloodstream.
- Y-90 resin microspheres contain the radioactive element yttrium-90, which delivers radiation over a relatively short distance in human tissue.
SIR-Spheres® Y-90 resin microspheres work from the inside, targeting radiation to the tumors.
- When given with chemotherapy, SIR-Spheres may shrink liver tumors more than chemotherapy given alone.1,2
- In some patients, SIR-Spheres may shrink the tumors enough that they can be removed by surgery at a later date.2-4
- Scientific studies have shown that treatment with SIR-Spheres may help you feel better and live longer.1,3,4
3. Cosimelli M et al. Br J Cancer 2010; 103: 324–331.
4. Sharma R et al. J Clin Oncol 2007; 25: 1099–1106.