The FDA has approved yttrium-90 (Y-90) glass microspheres (TheraSphere™, Boston Scientific) for the treatment of patients with unresectable hepatocellular carcinoma (HCC). The most common type of primary liver cancer, HCC is often treated with surgery, liver transplantation, chemotherapy, or embolization. The radioactive Y-90 glass microspheres are delivered directly to the liver tumor through a catheter. The treatment, referred to as selective internal radiation therapy or embolization, minimizes the damage to healthy surrounding tissue and does not require hospitalization.
"Neoadjuvant locoregional therapies are key to bridging HCC patients to transplantation or resection," write investigators of the LEGACY study, on which the approval was based, led by Dr. Riad Salem, Chief of Vascular and Interventional Radiology at Northwestern Feinberg School of Medicine in Chicago, Illinois. "The primary end points of LEGACY were to evaluate local tumor control and duration of response in unresectable HCC following radiation treatment with Y-90 glass microspheres as either a neoadjuvant or stand-alone therapy."
LEGACY enrolled 162 patients whose liver disease was classified as Child-Pugh A with solitary tumors (≤8 cm). Patients received treatment with Y-90 glass microspheres, and an independent blinded central review process was used to evaluate the pre- and post- treatment images. Primary end points were objective response rate and duration of response.
The overall response rate was 72.2%, with a duration of response of at least six months achieved in 76.1% of the patients with a confirmed response. Treatment was effective both as a solidary treatment in 50 patients and as a neoadjuvant therapy to transplant or resection in 45 patients. The intent-to-treat population experienced a median overall survival of 57.9 months and a three-year overall survival rate of 86.6%. The liver function of patients was monitored; 92.9% maintained albumin, and 85.3% maintained bilirubin.
"Patients with solitary, unresectable, advanced HCC treated with Y-90 glass microspheres had high response rates, clinically meaningful duration of response, and comparable overall survival to existing curative therapy," concluded Dr. Salem and colleagues in their presentation abstract from the 2020 European Society for Medical Oncology (ESMO) Congress. "Radiation treatment with Y-90 glass microspheres is an effective means of treating solitary HCC while preserving liver function."
For More Information
Salem R, Johnson GE, Riaz A, et al (2020). Yttrium-90 glass microspheres in the treatment of early and advanced hepatocellular carcinoma: the LEGACY study. Annals of Oncology (ESMO Congress Abstracts),31(suppl_4):S692-S693. Abstract 992P. DOI:10.1016/j.annonc.2020.08.1108
Boston Scientific (2021). Boston Scientific Receives FDA Approval for TheraSphere™ Y-90 Glass Microspheres [news release]. Available at: https://www.prnewswire.com/news-releases/boston-scientific-receives-fda-approval-for-therasphere-y-90-glass-microspheres-301249924.html
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