Clinical

Radioembolization with microspheres promising for liver metastases

Last Updated: 2008-10-15 15:59:10 -0400 (Reuters Health)

By Will Boggs, MD

NEW YORK (Reuters Health) - For some patients with inoperable neuroendocrine tumor liver metastases, radioembolization with selective internal radiation microspheres can achieve relatively long-term responses, according to a report in the September 1st issue of Cancer.

"This is a good example of the use of spheres to deliver treatment," Dr. David L. Morris told Reuters Health. "The microsphere delivery of a variety of agents will, I think, be of increasing importance and not just in cancer."

Dr. Morris from the University of New South Wales, Sydney, Australia, and colleagues assessed the safety and effectiveness of yttrium-90 radioactive resin microspheres in 34 patients with unresectable neuroendocrine tumor liver metastases.

At least half the patients who were previously symptomatic reported improvement at 3 months (18/33 patients, 55%) and at 6 months (16/32 patients, 50%).

By radiological assessment of the liver, 6 patients had a complete response, 11 patients had a partial response, 5 patients had stable disease, and 11 patients had progressive disease.

Mean survival was 27.6 months, the investigators say, with 14 patients dying from progressive metastatic disease after a mean of 14.6 months and 20 patients alive with a mean survival of 36.7 months.

There was no obvious contributing factor to account for the good to excellent response in 12 patients who remained alive with no recurrence of liver disease after treatment with yttrium-90 microspheres, the researchers note.

All patients reported some degree of abdominal pain from 1 week to 1 month after treatment, the report indicates, but only four patients experienced severe pain and vomiting.

"It is questionable whether any other therapy previously has achieved such useful results in patients with inoperable disease," the authors conclude.

"We would not consider SIR (selective internal radiation microsphere) treatment for patients with operable neuroendocrine tumor liver metastases," Dr. Morris cautioned. "The reason for this is that whilst we have had complete responses in some patients, SIR treatment does have some serious adverse effects, and we certainly don't yet know what the really long-term results are."

He added, "I suppose the most important thing I think we need to know is why some patients have done so superbly well and other patients haven't."

Cancer 2008;113:921-929.