Selective Internal Radiation Therapy (SIRT) is a treatment for advanced liver cancer that utilizes SIRspheres to deliver targeted, internal radiation therapy to the tumor.
SIRspheres are tiny polymer beads which contain a radioactive element called yttrium-90.
Marc L. Friedman, MD, Chief, Vascular and Interventional Radiology, leads our team of imaging physicians, nurses and technologists who specialize in this procedure.
A small skin nick is made in the patient's groin crease and a flexible catheter is manipulated painlessly by the interventional radiologist into the liver artery under x-ray guidance. The Sirspheres are then released and are carried by the bloodstream directly to the tumors in the liver where they preferentially lodge in the small vessels feeding the tumor and deliver their dose of radiation. This technique enables treatment with relatively high doses of radiation preferentially to the cancer cells over a longer period of time when compared with conventional external beam radiation therapy. 
The procedure takes approximately one hour to complete. It usually requires two sessions separated by approximately one month to treat the entire liver. The procedure is performed in the outpatient setting with most patients going home the same day.
Patients may be candidates for SIRT if:
- They have inoperable colorectal cancer which has spread to the liver and is not responding to chemotherapy. Other types of cancers that have spread to the liver may also qualify.
- The liver is the major site of disease
- Meet the pre-selection criteria established by the doctor's pre-treatment testing
