Radiation therapy underused for people with liver cancer awaiting transplant

People with liver cancer awaiting transplantation could benefit from non-invasive radiation treatments but are rarely given this therapy, according to a new analysis of U.S. national data.

“External-beam radiation therapy is a proven, established, safe and effective treatment option for patients with unresectable liver cancer, yet its under-utilization within this population—fewer than 4% of patients—highlights a real-world gap in treatment options available for patients with hepatocellular carcinoma,” study author Nima Nabavizadeh, M.D., told reporters at the American Society for Radiation Oncology Annual Meeting. Nabavizadeh is an associate professor of radiation medicine at Oregon Health & Science University in Portland.

For patients with localized liver cancer and advanced cirrhosis, “liver transplantation is the best and only chance for long-term survival,” Nabavizadeh said. But the supply of organs available for transplant is limited, and candidates often wait months or more than a year for a donor organ. And if a patient’s cancer spreads outside of transplantable size criteria or to another part of the body while they are waiting for a new liver, they are no longer eligible for transplant. Many patients, therefore, receive a bridging therapy to prevent the growth or spread of tumors while they await a donor organ.

Bridging therapy options include thermal ablation procedures, which use advanced imaging technology to guide probes through the skin and into the liver, to burn or freeze tumors at the site. Catheter-based treatments including transarterial chemoembolization, or TACE, and Y-90 radioembolization, where small particles are injected selectively into an artery directly supplying the tumor that cut off a tumor’s blood supply and trap chemotherapy drugs or radioactive substances within the tumor. External-beam radiation therapy, or EBRT, aims high doses of targeted radiation at tumor sites from outside the body using non-invasive techniques.

Nabavizadeh and colleagues analyzed data from the United Network for Organ Sharing to see which bridging therapies were prescribed most often. Of the 18,477 patients with HCC awaiting transplant since 2013, 85.4% received some type of bridging therapy. However, just 3.6% of those patients were treated with EBRT.

TACE was the most utilized therapy, used for 39.6% of patients. Thermal ablation was used for 12.8% of patients, and radioembolization was used for 8.7% of patients. Nearly a quarter of patients received a combination of non-EBRT therapies.

While the study did not explore why patients were prescribed one treatment over another, Nabavizadeh suggested it could be a result of which type of doctor a patient consulted. “Radiation oncologists are often left out of the management discussions for these patients,” he said. “When presented with choices, many patients want the non-invasive approach. They understand this treatment could really impact their quality of life. Radiation needs to be part of treatment discussions much more frequently than it is now.”

Read more at the ASTRO meeting website.