Drug & Device Development

Radioembolization promising for inoperable chemorefractory liver metastases

Last Updated: 2008-04-30 9:41:51 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Radioactive microsphere therapy appears to prolong survival in patients with unresectable, chemorefractory metastatic disease of the liver, findings from a prospective, open-label phase II study indicate.

In the absence of treatment beyond supportive care, survival of such patients is usually about 6 months, lead author Dr. Kent T. Sato, at Northwestern University in Chicago, and associates note in the May issue of Radiology. In the current study, overall median survival was 300 days.

The trial included 137 patients who underwent 225 infusions of yttrium-90 glass microspheres into the hepatic artery (TheraSphere, MDS Nordion, Ottawa). The patients had ECOG performance status scores of 0-2 and limited extrahepatic disease.

"The actual biologic response rate of treated tumors was 87%, with those lesions showing at least some decrease in size after therapy," Dr. Sato's group reports. Median survival rate was 457 days for patients with colorectal cancer, 776 days for neuroendocrine tumors, and 207 days with other types of tumors.

Patients with an ECOG score of 0 had a significantly longer median survival compared with those with higher scores (731 vs 137 days). "This trend was maintained across all tumor types and reached statistical significance, supporting the notion of poor prognosis once cancer-related symptoms appear (ECOG > 0)," the research team maintains.

Median survival was more than two-fold longer among patients age 65 and older versus younger patients, and among patients with four or fewer tumors compared with those with more.

The degree of tumor vascularity was not predictive of survival. Therefore, the authors state, "The radiologic appearance of tumors may not affect the delivery of microspheres and should not be used to include or exclude patients for this type of therapy."

The treatments were well tolerated, with only two major complications (radiation cholecystitis and GI ulceration). The most common complaints were fatigue, vague abdominal pain, and nausea, but almost 30% of patients reported no complaints.

"Patients with good performance status and liver-dominant disease may obtain some clinical benefit from radioembolization," Dr. Sato and his associates conclude.

Radiology 2008;247:507-515.