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SIR-Spheres® Y-90 resin microspheres

About SIR-Spheres

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

About SIR-Spheres
  • 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.1,3-5
1. Wasan et al. Lancet Oncol 2017; 18: 1159–1171.
2. Garlipp B et al. Br J Surg 2019; 106: 1837-1846.
3. Cosimelli M et al. Br J Cancer 2010; 103: 324–331.
4. Sharma R et al. J Clin Oncol 2007; 25: 1099–1106.
5. Vilgrain V et al. Lancet Oncol 2017; 18: 1624-1636.