The FDA has approved SIR-Spheres (Sirtex Medical Inc, New South Wales, Australia) for the treatment of unresectable metastatic liver tumors from primary colorectal cancer together with intrahepatic artery chemotherapy with floxuridine.
The approved device consists of biocompatible microspheres containing yttrium-90 of 20 to 40 µm in diameter. It is implanted into a hepatic tumor by injection into either the common hepatic artery or the right or left hepatic artery via a chemotherapy catheter port. SIR-Spheres distribute unevenly in the liver, and its density in the tumor can be as much as five or six times that in normal liver tissue. The product remains permanently in the liver.
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