yttrium-90 resin microspheres

Yttrium-90 resin microspheres, commercially known as SIR-Spheres, are a therapeutic radiopharmaceutical used for selective internal radiation therapy (SIRT), also called transarterial radioembolization (TARE). Developed by Sirtex Medical, the product consists of biocompatible resin microspheres (20–60 microns in diameter) containing the radioactive isotope yttrium-90, a pure beta emitter. The microspheres are injected through a catheter into the hepatic artery, where they preferentially lodge in the microvasculature of hypervascularized liver tumors. The yttrium-90 delivers a high, localized dose of ionizing radiation (mean tissue penetration of 2.5 mm) to the tumor, causing cell death through DNA damage while sparing healthy liver tissue. It is primarily used to treat unresectable hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), and liver metastases from colorectal cancer (mCRC) and neuroendocrine tumors.

Brand names

SIR-Spheres

Other names

yttrium-90 resin microspheresyttrium90 resin microspheresyttrium 90 resin microspheresY-90 resin microspheresY90 resin microspheresY 90 resin microspheres90Y-SIRTSelective Internal Radiation TherapySIR-Spheres Y-90 resin microspheres