Yttrium 90 microspheres are used in treatment of:

Selective internal radioembolization is a promising new treatment modality for patients with inoperable primary or metastatic liver tumors. The treatment is a minimally invasive transcatheter therapy in which radioactive microspheres are infused into the hepatic aeries a transfemoral percutaneous approach. The yttrium 90 microspheres are directly injected into the hepatic aery branches that supply the tumor. Once infused, the microspheres deliver doses of high-energy, low-penetration radiation selectively to the tumor. The main indications are inoperable HCC118 and colorectal cancer hepatic metastases for which systemic chemotherapy has failed Ref: Schwaz's principle of surgery 9th edition, chapter 31.