Drug & Device Development

Yttrium-90 radioembolization effective for neuroendocrine liver metastases

Last Updated: 2010-06-10 19:59:52 -0400 (Reuters Health)

By Will Boggs MD

NEW YORK (Reuters Health) - Yttrium-90 radioembolization shows promise for treating unresectable neuroendocrine metastases to the liver, researchers report in the May Annals of Surgery.

Dr. David L. Morris from St. George Hospital, Kogarah, New South Wales, Australia told Reuters Health by e-mail that this approach might be used for "a select group" of patients.

"Patients with low hepatic tumor burden, well-differentiated tumor, female gender, and no extrahepatic disease benefit most from treatment," he and his coauthors say.

The researchers assessed the factors affecting response and survival in an open-label phase II study of 48 patients with neuroendocrine liver metastases treated by yttrium-90 radioembolization.

Patients received an average yttrium-90 dose of 1.94 Gigabecquerel (GBq), equivalent to 5.24 curie, at a mean of 48 months after diagnosis of the primary tumor.

Three patients (6%) required temporary balloon occlusion to reduce the percentage of arteriovenous lung shunting to below 20%, although the overall estimated percentage shunting to the lungs was only 7.3%.

Twenty-six of 47 patients (54%) followed beyond 1 month after the initial radioembolization procedure responded completely (7 patients, 15%) or partially (19 patients, 40%).

"Isn't it amazing that durable complete responses occurred?" Dr. Morris said. This is "very different from TACE (transcatheter arterial chemoembolization)."

Eleven patients (23%) had stable disease, and another 11 had progressive disease after radioembolization.

Survival was 87% at 1 year, 62% at 2 years, and 46% and 3 and 5 years.

Serum alkaline phosphatase levels increased significantly over the 6-month study period, but there were no significant changes in serum albumin, aspartate transaminase, alanine transaminase, or total bilirubin. Only 1 patient developed grade 3 serologic toxicity after treatment.

"The encouraging results of this study and others warrant further prospective investigation, particularly when other treatment modalities for unresectable neuroendocrine tumor liver metastases have yielded inconsistent results," the researchers conclude.

Ann Surg 2010;251:910-916.