(radioembolization) A combination therapy for cancer treatment that couples radiation therapy and embolization through the introduction of radioactive microspheres directly into vessels supplying the tumor, allowing for the delivery of high dose radiation without irradiating healthy tissue.

(radioembolization) A type of radiation therapy used to treat liver cancer that is advanced or has come back. Tiny beads that hold the radioisotope yttrium Y 90 are injected into the hepatic artery (the main blood vessel that carries blood to the liver). The beads collect in the tumor and the yttrium Y 90 gives off radiation. This destroys the blood vessels that the tumor needs to grow and kills the cancer cells. Radioembolization is a type of selective internal radiation therapy (SIRT).