Radioactive Holmium Microspheres for the Treatment of Unresectable Liver Metastases

Radioembolisation is a known method for the treatment of liver tumors and or livermetastases. Currently small beadlets called microspheres are used that are loaded with the beta radiation emitting Yttrium-90. Holmium-166 microspheres have different physical characteristics including good visualisation in gammacameras due to the gamma emission. Because of the higher specific activity higher radiation doses to the liver will be used compared to the standard Yttrium treatment. It is hypothesized that higher doses of irradiation have an improved antitumor effect.