Influence of degradable starch microspheres (Spherex) on the retention of pertechnetate in a solitary rat liver tumor.

ABSTRACT

In a model of secondary liver cancer in the rat an evaluation was made of the influence of degradable starch microspheres (Spherex) on the drug retention in tumor and liver tissue. Sodium pertechnetate was used as a drug model substance and was injected into the hepatic artery alone or with degradable starch microspheres (DSM) in a dose of 6 or 12 mg. The distribution of pertechnetate was measured by a gamma-camera equipped with a high resolution collimator. In rats with liver tumor the total elimination of pertechnetate from the liver was delayed when compared to rats without tumor. The tumor concentration of pertechnetate was higher than that of the surrounding liver tissue, irrespective of the presence of DSM. With a DSM dose of 12 mg there was a significantly higher retention of pertechnetate in the tumor during the whole observation period compared to pertechnetate only. The results of this study indicates that DSM can be of value in regional liver chemotherapy to increase liver tumor drug exposure and to reduce systemic toxicity.