Higher doses of yttrium-90 (Y-90) than previously used in intra-arterial radioembolization to treat persons with liver tumors provide results when chemotherapies have failed, according to study findings presented at the recent annual scientific meeting of the Society of Interventional Radiology, held in Chicago.
Although radioembolization is a palliative rather than a curative technique, several subgroups included in a 4-year, 151-person study by Riad Salem, MD, MBA, and colleagues showed high rates of progression-free survival with fewer side effects. In one case, a 60-year-old woman with advanced liver cancer that had metastasized from neuroendocrine tumors had lesions that were progressing as she continued to undergo standard chemotherapy treatments. At the higher dose of Y-90 used in the trial, the lesion progression reversed and the tumors shrank with no adverse events.
This outpatient treatment combines the radioactive isotope Y-90 into microspheres—beads approximately the width of five blood cells. The microspheres deliver radiation directly to a tumor. “We knew that this unique interventional radiology treatment … was one of the best ways to give patients a treatment that doesn’t harm healthy cells,” affirmed Dr. Salem, the director of interventional oncology in the radiology department at Northwestern University, in a statement describing his group’s findings. “Now we know that patients can actually tolerate much higher doses of radiation than previously thought, which provides results in patients progressing on standard chemotherapy.”
The microspheres are injected through a catheter into the hepatic artery. The beads lodge within tumor vessels and radiate the cancerous cells. This “internal radiation” technique permits the use of a higher, local dose of radiation that does not endanger healthy tissue.