An Explanation of SIR-Spheres

Andrew Kennedy, MD, physician-in-chief, Radiation Oncology, Sarah Cannon, director, Radiation Oncology Research, Sarah Cannon Research Institute, explains what SIR-Spheres are and how they are used.

Clinical Pearls:

• SIR-Spheres are microparticles that have radiation combined in them that are delivered to tumors in the liver using an artery that feeds into the liver that goes just to the tumor.
• This radiation is permanent, but is only delivered to the tumor so it is very safe.
• The SIR-Spheres are combined with water and delivered to the tumor.
• These spheres are small enough to get into the tumor, but too large to escape the tumor. The radiation is given off until it runs out.